The SEC can target centralized staking easily, but it's going to have a hard time doing the same with "De-Fi" staking platforms. They might try to go after developers, though. But their chances of success would be low, especially if developers of the project are anonymous. I'd say the recent actions of a US government agency would only stifle the growth of the crypto industry in the long run. They've gone against mixers, and now they're going after centralized staking. What makes you think they won't go after privacy coins too?
Monero would be better off focusing on censorship-resitance by staying a PoW coin forever. It could last a lifetime if it follows Bitcoin's footsteps. Even if developers defect to PoS, there's nothing stopping the community from rejecting changes to the code or simply creating a new hard fork that would continue PoW mining. Who knows if Monero lives alongside Bitcoin and other oldies for generations? Just my opinion