I started digging into opensource password managers and found that they all suck major ball sack. I ended up picking nothing. My two runner-ups were bitwarden. It works on Linux, Android, whatever apple's shit runs on, and even runs on PC's with the OS that you usually delete first thing. But the major drawback is that I can't trust it. It's got a "premium" version, and that has always meant a slow steady spiral into "you must pay now that we have you by the balls" situation. Another drawback is that it's centralized, kill the company and so go your passwords I suppose.
The other runner up is called liso. This one comes with two major drawbacks. One is that is browser only so far. The other one is that it doesn't work on Linux yet. Such a shit shit option. Everything else out there wants you to pay for encryption.
I did end up learning about pass on Linux. It creates encrypted passwords and there's some compatibility with guis and maybe available on Android??? Big question mark. I've tried nothing yet. My password list seems to grow daily.
Bitwarden is open source (server, plugin and app) and can be self-hosted so it's not centralised in any way that matters.
Also, I think an honest freemium offering is the best way to do it - have those that are willing/able to pay subsidise those who aren't. It doesn't have to be a slippery slope, and that's not exactly common in the open-source world. After all, you can just fork it and go your own way if you're not happy. Also, running servers isn't free, and being able to remunerate the devs a little is no small thing.
So, in summary, use Bitwarden. You can set up your own server and install the plugin/app yourself if you want.
This is what I use as well. As it does not come with any cloud storage (a feature imo) I sync it with syncthing - another great foss, privacy-friendly project.
I used to use KeePassXC, it works fantastic. After a few too many friends and family members started asking me about internet safety due to getting their accounts compromised, I spun up a Vaultwarden instance for us to share.
Cannot go wrong with KeePass (including derivatives). Works on all my devices, no cloud nonsense, everything is local and I can use Unison and Syncthing to sync it all up.