I've heard that Bitcoin will finish mining in 2140, which is certainly a long way off. There's still a chance for us to continue dca BTC, as there's a strong possibility that in the future we'll see a higher BTC price than today, as BTC is constantly being mined, and we'll eventually see the BTC supply dwindle. Currently, I know there's only a small amount of unmined BTC left, approximately 1,100,000. While the number currently mined is 19,900,000, there's still time to accumulate BTC.
Mining will never end as long as the BTC-network exists. Transaction confirmation services will always be needed, and therefore mining. So even after the last bitcoin is mined, bitcoin will be able to accumulate by receiving bitcoins in miner fees.However, I'd like to know if there will be BTC miners once the supply is fully mined, and will the fees for sending from wallets to exchanges be high? I also wonder if the price fluctuations will be similar to the current bearish and bullish market. Currently, BTC is widely traded, buying at a low price and selling at a high price. But will BTC trading be possible in the future, similar to daily trading? I think this is worth discussing... 
Miners will NOT appear because they will not disappear. That is, miners will remain.Commissions will depend on the load of the meme pool (mass use of bitcoin by users). Perhaps new technologies will be introduced that will reduce the cost of commissions, so, most likely, commissions will still remain at acceptable levels.
Most likely, the market will be more stable in the future and fluctuations less noticeable than now. This may be due to a higher level of capitalization and very impressive capital will be required to destabilize the bitcoin rate.
Trading will never disappear, even with low volatility, there will be those who want to earn extra money on rate fluctuations.