Or should we be focusing on developing new solutions and improvements to further safeguard our privacy in the Bitcoin ecosystem?
Here's the thing, Bitcoin is not a centralized orgs, if some people think coinjoin or mixer is not enough they'd definitely build their own solution for privacy issues. I'm pretty sure some are already doing that, so you don't have to worry about the lack of innovation related to privacy tools.
there are a few methods of obfuscating the movements of funds that do not sound like "mixers".. but if you read any of the "privacy"/"mixer" topics on this forum, you do not see much discussion about innovating new tools to bypass regulated lists. instead you see mixer operators screaming that everyone should use their service more..