RE: Why the value of Bitcoin keeps dropping？

I think the way we misuse words like "wallet" is a key problem. People label custodial websites who keep your money for you as "wallets". It would be as appropriate for me to call my bank account a "wallet." For the same reasons these are not "wallets." Instead these are accounts. They can be frozen or confiscated at anytime. In the case of BTC, I think even more so.