Something like adding more BTC in an equivalent amount for those lost BTC, or something similar.
Would it be positive for the currency or could bring some caos?
Of course, that will not happen, the Bitcoins lost due to losing the private key will be lost forever. There is no compensation for that Bitcoin, because from the beginning Bitcoin was created in such a certain quantity and no one, not even Satoshi, can fix it. Because of this, Bitcoin has value, and the actual number of Bitcoins that can circulate on the market will be much lower than 21 million. This is an advantage for those who are holding Bitcoin, because I believe the price of Bitcoin will grow many times more than its current price.
Yes that's right. lost bitcoins there is no compensation for those Bitcoins because the final supply of bitcoins will not increase. Whether you admit it or not, a lot of bitcoins were lost, especially in the early days of Bitcoin, so many people didn't realize that the value of bitcoin would be what it is today, so many of them forgot. Seed Phrases, theft, and transaction errors.
This is just an assumption as an example, if 5 million bitcoins can never be recovered again, then that would lower the maximum limit from 21 million to 16 million. So it is true as you said that the price of bitcoin will increase many times because the number of bitcoins is increasingly limited.
Correction, the maximum supply of Bitcoin will not decrease from 21 million to 16 million just because there are 5 million Bitcoins that was considered lost forever or that can never be recovered. Those 5 million Bitcoins will only be treated as less amount in the total circulating supply. The total supply will remain at 21 million and will not decrease due to the lost Bitcoins.