As for the original question of this post, I have not used Proton Pass personally, and have not used Bitwarden recently.
Regardless, I would recommend you use the best tool for you personally. If you find Bitwarden nicer to use than Proton Pass, or the reverse, then use what works for you.
But more generally, I have to agree with this:
You should really use the best service for each one of your singular needs, and not use the same one for everything.
While Proton’s (still developing) ecosystem is nice, you should really evaluate Proton Mail, Calendar, Drive, Pass, and VPN as separate products. It’s fine to use them all, if they’re genuinely the best options for you (and they are pretty good).
But, if Bitwarden works better for you, or Mullvad works better for you, etc., then you should use them. Using the whole ecosystem is not required, and not really recommended (if it makes sense for your use case to use other products), since you’ll be relying on them for a lot of your stuff.
My personal setup (has been moved to a new thread).