isn't it possible to have some compensation for those lost BTC?
Compensation, like, how? Do you mean rewarding those who have lost their bitcoin or adding those back to the supply? Whichever the case might be, it won't work as you can't add more to the supply, nor is anybody willing to donate his or her bitcoin to those who lost theirs.Quote
adding more BTC in an equivalent amount for those lost BTC, or something similar.
One thing that makes Bitcoin unique is its limited supply. It was possible that it could have been manipulated long ago, and the limited supply is what contributes to its price value as demand increases, so it will become scarce in the market.Quote
Would it be positive for the currency or could bring some caos?
If that is ever made possible to increase the supply for whatever reason, there will only be negative impacts on the network. Those lost bitcoins, according to Satoshi, are a contribution to the network; they're considered a donation for the rest of the holders to gain more value. 
