Take note that it's not that miners will stop their work once all bitcoins are mined. Currently, miners get the newly generated coins and the transaction fees. At that time, miners will still get the transaction fees.


That's how bitcoin is designed. The initial block reward was 50 BTC and it's halved every 210,000 blocks.

It may worth mentioning that the total supply of bitcoin will be exactly 20,999,999.9769 BTC.

It's worth to note that we'd never reach exactly 21 million due to the 8 decimals limit; 0.0231 BTC deducted there. Also, there have been thousands of bitcoins that have been provably burned (i.e., block rewards which didn't include the subsidy or, less than subsidy, or mistakes in Script language), and right as well as probably thousands of bitcoins that have been lost non-provably.

Because of the difficulty adjustment. Read about it here. TL;DR: the more the mining, the more difficult it is to mine a block, and oppositely, the less the mining, the more easier it is to mine a block. This ensures that every block will be mined in about every 10 minutes, regardless of the hashrate. Now add halving to the equation, and you get ~2 million coins until 2140.

True. If some reports about mining companies are to be trusted, we can conclude that their recent mining profit is still negative, but they keep their business afloat by selling coins mined a few years/months before. I can't say for sure if this is a spin from the media or just business trying to deter competitors from competing on their business though.

At the end of the day, the market will find the equilibrium and some miners will definitely stop mining due to mining costs, the question is whether the security of the network is good enough to sustain the network when that does happen. Considering how the BTC hashrate keeps rising though, I doubt we'll see that happen in the near future. CMIIW.

I don't think that you need to wait till 2140, most likely in the next 3-4 block halvings, "almost all" bitcoin are going to be mined or at least 99% of it. And that 1% could take centuries to be mined.

So in this case, it might be difficult to get bitcoin decades from now. Supply are dwindling, but that 21 million might not be reach technically.

All known issues related to this subject have been solved so far.  Say US Government was able to secretly build enough mining equipment to double the current mining hash rate.  One day they plug all of them in and now mining happens two times faster.  BUT!  Every 2016 Blocks, mining difficulty is adjusted.  This means their strategy would only work for 2016 Blocks at MOST.

Then you have the Halving.  This solves another solution.  Even if a Block is mined every 10 minutes on average.  Halving the mining reward every 4 years means the process is slowed down in half every four years.

These two combined make it about impossible to cheat the system.  Sure.  The date this happens in the year 2140 is not precise mostly because a Block does not take EXACTLY 10 minutes to be mined.  Sometime it takes 30.  Sometime it takes only 5.  But average is 10 anyway.  So the year will be somewhere around 2140.

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Regards,
PrivacyG

First, let's talk about your writing and grammar. Your English is not bad but you should improve it, especially grammar that temporarily damages what you want to express. I can guess what you want to discuss but improvement should be made.  

• Grammarly.com. I advise you to use this one together with Grammar book

Second, you misunderstand about how Bitcoin blockchain works, how difficulty is set up to retarget. Hashrate on the network can rise or fall but difficulty retarget algorithm is always in place to do its task every 2016 blocks (which is about 14 days).

Bitcoin network's Total hash rate (TH/s). Choose all to see how it has risen with time. Then see how Network difficulty adjusted in history with some deep falls.

If you want to discover some reasons behind this (like flood season in China mainland, mining crackdown), explorer in my topic

• The history of Bitcoin difficulty adjustment (in percent)

A cool tool for Difficulty estimator is helpful for you to recognize that Bitcoin network can operate fine with either increasing or decreasing total hash rate.

Halving is the reason mate, on every halving, the amount of bitcoin released to miners is reduced by half, so by this, I believe you should understand why it took just 10 or a little more years to mine 19 million bitcoin, but will several years for the remaining 2 million bitcoins to be mined, this is clearly because, the blockchain reduced the amount of bitcoin miners get, from now on, they are earning far lesser bitcoin than they earned 10 years back.

There is no need for miners to retire due to the halving.  While reducing the block reward may make Bitcoin mining less profitable, there are still many incentives to continue mining Bitcoin, such as transaction fees and the prospect of a long-term increase in the price of Bitcoin.

 Furthermore, Bitcoin miners are often large companies or groups of miners who have invested substantial sums in mining equipment and infrastructure.  These individuals may have a long-term view and consider the halving as an expected event in their business strategy.

The image below gives a clear reason why it will be very difficult to mine the remaining 2 million Bitcoin before 2140, because after each halving, the reward for mining is divided into half, of which the first reward for mining Bitcoin was 50 BTC in 2009, and 4yrs later after 2012 halving, the reward got divided into half I.e 25 BTC, and likewise 2016 and 2020 halving reward, including next year's halving which its reward is expected to be 3.125 BTC.



Why after next year's halving, the next are as follows;
2028 = 1.5625  BTC
2032 = 0.78125  BTC
2036 = 0.390625  BTC
2040 = 0.1953125  BTC
2044 = 0.09765625  BTC
2048 = 0.048828125  BTC
2052 = 0.0244140625  BTC
2056 = 0.01220703125  BTC
2060 = 0.006103515625  BTC

It is estimation that is certainly not correct!

Estimation is based on many assumptions which can be true or untrue in reality. I made my estimation in the past and you can use similar methodology to make your estimations with latest on-chain data and UTXO bands you want to use.

• Investigate, assess news. Don't simply read and make wrong decisions

My estimation 3 years ago.

• https://hodlwave.com/. I used this site in 3 years ago estimation but it stopped updating information since 2020.
• Two alternatives
  
  • https://unchained.com/hodlwaves/
  • https://www.lookintobitcoin.com/charts/hodl-waves/

• Controlled supply
• Equivalent network time

Visually