I do prefer the idea of using something like Keepass and not relying on a service but I found it rather frustrating to manage between my multiple devices. I knew if I were to actually make use of a password manager it needed to be a smooth experience because otherwise I would just return to using Chrome's built in one out of laziness.
After researching the main online managers I decided to go with Bitwarden. It is open source so if it does do something dodgy I would hope it is found and reported. I do not have the time nor expertise to audit all of the code myself so I have to put some trust in others.
Plus while it would be a real pain in the ass if accounts were compromised due to the developer being an asshole/idiot it wouldn't destroy my life. I have a strong password on my primary email account (not stored in Bitwarden) along with 2FA. Most of the logins stored in Bitwarden are for things like Hacker News, Reddit, Slack (personal not work), etc. Randomly generated 18+ character strings that are a pain to enter manually, especially on a phone.
As I mentioned in my other comment, the only gotcha is to make sure you set up your syncthing ignore file to ignore the KeePass database lockfile.
You could always upload your encrypted key database to dropbox, and keep your private key on your phone, on your computer, or on a USB stick, if you want automatic sync.
Just make sure to configure Syncthing to ignore KeePass lockfiles.
I am not a security expert, so I cannot assert their trustworthiness myself. I know that you can run your own server. But even then, without auditing the code, configuring a firewall, and checking network logs, I cannot assure the server and the clients do not call home. And all of those solutions are both prohibitively time-consuming and way out of my area of expertise.
How did you decide Bitwarden was trustworthy? How can I stop worrying and give them my passwords already?