1. sure, it's great that it is open source and that I could self host, but honestly, it's just not worth the trouble for me and I'd rather pay 10-20 euros for someone to take care of that for me. Self hosting my password manager would take a significant time investment and constant worry whether I'm doing it right. It might be because I'm primarily an app developer now and not a backend expert anymore.
2. Most big projects like Bitwarden are alive because there is a company and many full time employees behind it. Once that's gone, relying on a couple of passionate volunteers might not be enough to keep the project alive.
All in all, I've been using Bitwarden since the LastPass fiasco, I'm very happy with it, paid user with my family, but if I had to self host or volunteer, I'd not have the bandwidth to do so and I'd rather switch to another solution, even if it would mean I need to pay.
I think that when people say "it's open source, I could just self host and maintain the project" often underestimate how much effort that really is. Sure, it's possible, but will you actually do it?
Then I must have overestimated the effort needed for an experienced dev to set things up. I assume I would need a day to figure out how to best self host. Thanks for the info, I'll give it a try this weekend.