Bitcoin is already being adopted globally and about your first question, that's why they intervene and impose or suggest a ban that's related to it. There is one thing that they're forgetting about this matter. There's no way to stop the global adoption of bitcoin, they might ban it from the north but it's going to be adopted and freely used in the south. And that's the actual thing that's happening today, bitcoin's community is going bigger and bigger and they can't stop and deny that fact.

I think we already know what the answer is.

If the so-called banks were not being threatened by Bitcoin, do you think they would be talking of banning it. The fact that they are feeling the impact of Bitcoin even before being fully adopted says a thing or two about them thinking of becoming less relevant.

Things are more complicated than that. There are multiple cases that decision makers in EU are concerned about and each are different. For example there is a global rising concern over the token scams and money that is being laundered using tokens (these days NFTs) that leads to talks about banning trading of "altcoins" not bitcoin.

The mining concerns in EU mostly come from the fact that most of EU has been struggling to keep the lights on and there is a rising concern about increasing gas and other fuel costs that increases the electricity cost and the ability of producing it. The uninformed EU decision makers think banning bitcoin "mining" would alleviate the situation.

I don't think bitcoin has that capacity yet. It is too small and too little adopted to do that.

Bitcoin already is a global currency, I think you mean "when bitcoin reaches mass adoption". Neither banks nor the government can do anything about the inevitable, they can only make it slower.

In the case of Russia, it was a bluff: Russian government to legalize its crypto economy

Bitcoin has come in handy for them now that the US is threatening to take them out of the SWIFT system.

As for the rest of the central banks, I think they will eventually even buy Bitcoin for their reserves. It won't be soon, but they will. When the Bitcoin was born, they didn't even give it any importance. When Bitcoin became bigger they realized the competition it posed and associated it with fraud and scams but they realized they could not stop it and in the end it has been regulated around the world. Now financial institutions that previously associated Bitcoin with scams are preparing custodial services to offer, Bitcoin ETFs, etc. The last step will be for them to buy/mind bitcoin.

The confrontation between the central banks of states and decentralized cryptocurrencies will be for a long time. Cryptocurrency, of course, is not liked by banks, because they lose their complete dominance over citizens in the financial sector, and also lose part of their earnings. Therefore, they will continue to discredit the cryptocurrency. However, the cryptocurrency is spreading relatively quickly around the world and therefore it is becoming increasingly difficult to ban it. After all, very smart and influential people also invest in cryptocurrency. But on the other hand, central banks also have nothing to fear. They, being actually a part of the state, are under its reliable protection. Therefore, it will be better if banks and cryptocurrencies learn to coexist peacefully.

Winning the war against Decentralized Finance (DeFi) and Bitcoin are two different things.

I don't think the banks have anything against DeFi on Ethereum. Its far more easier to regulate and bring to the mainstream as it is already pretty centralized. There are a few top API providers that serve as the backbone infrastructure for every product out there. They can easily get particpants' information from those centralized services. So they would in fact be hailing DeFi rather than fighting against it.

When it comes to Bitcoin, that is definitely a pain point. Bitcoin is "money" that they have zero control over in terms of issuance and interest rates. Bitcoin doesn't treat the central bank any differently than it does you and me. That is scary for organizations, institutions and whole academician/ economist communities who have built decades worth of careers and make millions in consultation fee to keep the current system aligned towards high growth (at the expense of those at the bottom) as well as provide a sense of policy stability to the highly sentimental markets that are run by a great many number of players.

I don't think anybody can blame them for being extremely cautious or wary of it. Bitcoin threatens to provide an alternative as well as a disruption. Thus, then banks will never adopt Bitcoin or give it acceptance. Its the people who have to start saving their share of "Digital" gold and then wait for the banks to grow themselves around this new phenomena rather than run scared due to its novelty.

They can keep on what they're doing about discrediting bitcoin. That's all they can do for now but just as the other financial institutions that are wisely adopting.
They've realized that it's not going to be a wise solution while bitcoin is thriving. The best solution for them is to just adopt and accept it, there's no need for them to think of such matters against bitcoin since everyone is starting to learn and know more about it.

A fear that Bitcoin becomes their threat to the financial system, that's is normal for those countries that didn't understand what is Bitcoin and how it is useful and not become a threat.  Yes, that's a challenge for them on how to enforce regulation since we know that this technology isn't regulated or can't be regulated.  That's the point of view of the central banks towards Bitcoin but when they understand, it will surely change their mind, look at those big giant companies who criticized Bitcoin before, Google, Facebook, and even Youtube but now, they are fully accepted Bitcoin.

Possible from time to time, if their people keep using it without knowing them and knowing the fact that controlling Bitcoin is only foolishness might change their mind towards adoption.

I think a lot of people will need a third party to control their money, even if Bitcoin becomes truly mainstream.

Central banks will continue to exist in our lifetime, but Bitcoin will continue to grow each year and eventually will establish itself as a third way of payment: Cash, Card, Bitcoin.

There will be pros and cons for each method, some people will prefer different ones at different times.

Well, I think that the problem is that the central banks governors are misunderstanding decentralized cryptocurrency. I did see the news about the Hungary’s central bank governor who was calling on the EU to ban crypto mining and everything cryptocurrency. Most of them have been like this right from time and they are always making moves that would make leaders to ban cryptocurrency, but over the years cryptocurrency especially Bitcoin has stood strong, and even being accepted in a lot of countries.

I believe that their plan of trying to stop Bitcoin and banning it in their countries is not going to workout. Bitcoin will still continue its growth, because I believe that there are people who truly acknowledge it and as time goes on those who don’t understand what it is all about will also get to know it.