If ppl prefer to use Bitcoin because it's decentralised why can't it be updated in future to obfuscate spends. It's still going to be decentralised.
I know ppl use Monero for final spend or convert back to BTC because it's a privacy coin. Swaps from BTC to XMR help if you're wanting privacy for final spend but if you're trying to avoid using tumbles it costs more if XMR value went low if you're swapping XMR back to BTC.
Agreed, decentralization is very important. Monero is the only one besides Bitcoin that even comes close IMO. Most are centralized scams.
I'm more concerned about privacy here. Yes I think you can achieve privacy with Bitcoin, but it's not by default & it's not easy. Also with high fees, achieving good privacy is even more costly.
I know a lot of Bitcoiners secretly use Monero as a privacy tool for their final spend, that's another reason why I don't think this discussion belongs in the altcoin section.