It wont happen, because fiat is our traditional currency which can be used anywhere in entire country while crypto currency will depends on the demand and supply and the value is not stable, crypto currency is not yet accepted in different businesses which only offered in limited company who are aware in this digital currency.

I always see this to happen probably in about 25 years later, everything changes so if governments really do see blockchain to be the future technology then we may see the changes in less than 25 years. Let's say its not tether nor the XRP, maybe they will start having their own. Developers today can come out of something beyond what we can think of.

Its not that easy to replace Fiat, will take long long time. most of the banks would consider crypto as their enemy

Crypto will become more famous but it will never replace fiat because of price crypto is not uniform and I don't think it would ever be. And then there would be problem of scalability too.

I don't see the point of focusing on something that won't ever happen and doesn't need to happen.

Who cares what fiat is doing when we can use Bitcoin right now as money already? It's people's toxic mentality that needs to change, because the less people spend their coins, the less merchant incentive there is to jump on board. In other words, people should look in the mirror and understand what the underlying problem of everything is. It's YOU.

Everything right now is in our own hands and we can make or break this ecosystem. Governments must be laughing their asses off with how people here just use crypto for speculative purposes.

Firstly, I really do not see the likelihood of this happening and even if it did eventually get to happen at all, I am sure by then, all the worries you have stipulated would be something each person would have gotten used to, most especially when it comes to the idea of your record being opened to the whole world knowing your worth. Do not forget though that with just a click, public addresses can be changed and do not also forget that not all cryptocurrencies are pseudo anonymous.

Firstly, I don’t see that happening and I think this will never happen. Cryptocurrencies can never replace fiat. At the most both will co-exist. If there is only one to stay then it will definitely be fiat and not crypto. Secondly, anyone cannot see you holdings of Bitcoin. Bitcoin is pseudonymous implying that only the person with whom you are transacting in Bitcoin can see your holdings and not everyone.

It might happen but it might take a very long time, digital currencies continue to grow and many governments in the world begin to study the use of cryptocurrency for their people.
But, fiat money is a currency that has been used by humans for a long time, each country has its own currency and has used fiat money for all their daily needs, they will still love fiat money under any circumstances.

If any government believes that cryptocurrency could be regulated then consider it be Hoax! You may regulate a wallet, exchange, forum, chats and take data from them but you can't regulate blockchain.

Blockchain provides such invincible technology that no outer force can harness it. Every data on blockchain is Pseudo-Anonymous. Though it could be tracked upto certain degree using Hash or Transaction ID but real identity could be easily hidden in blockchain.

I think crypto can't replace fiat anymore, because in every countries must have their currency and that currency is backed by their goverment.
If this happen, I mean crypto has replaced the fiat I can't imagine that people who don't understand about it then it will make people do crimes to rip their asset.