Is anyone just using the browser's built-in password manager and calling it done? Password Managers

For your description, honestly, not a huge amount, and the enthusiast default is a real phenomenon. What you gain is portability between ecosystems, sharing that is not a screenshot, storage for things that are not website logins, and a vault that does not unlock every time your browser profile does. What you keep is convenience so good that you actually use it, which is the feature most people abandon a dedicated manager over. Using the built-in one properly beats owning a better one you fight with.

Turn on the reauthentication prompt for autofill and the breach alerts, whichever you stay on. Those two settings close most of the practical gap for a single-person, single-ecosystem threat model, and almost nobody enables them.

One practical thing the built-in ones do less well is anything that is not a username and password. Recovery codes, software licence keys, the passport number you need at 6am, a note about which email address you used for a utility. I moved for that rather than for security and would not go back.

The migration cost is what should decide it, and it is lower than people say. Export to a file, import, delete the browser copies, done in twenty minutes. The reason to do it before you need to is that the day you switch phone platforms or take a job on a different operating system, doing it under time pressure is miserable.

Do it before you have 400 entries, not after. Everything about this gets worse with volume and mine was a two-evening job by the time I got around to it.