Keychain Access has been there since the beginning of OSX/macOS. It's quietly been storing email and wifi passwords this entire time. Many, before there was an alternative like 1Password, used the app to store other info within as well through secure notes. Passwords in iOS and Safari, along with Keychain sync in iCloud have expanded the keychain functionality over the years and it's been fine for ~25 years or so. I have faith they won't suddenly screw this up and comparisons to less critical stuff like Screen Time aren't really valid here. And sherlocking? I don't think so. When 1Password came out, it was clearly inspired by Keychain Access that had been there for years prior with similar functionality and even user interfaces.

This is definitely a factor and applies to regular support help as well. I sent 1Password an email several years ago about an issue and got a prompt and helpful response back. It was a much better experience than I would ever expect from Apple (or Google/Microsoft/etc).

I'm not really a fan of 1Password overall though. The product is still fine but has gotten gradually worse over the years and their corporate posture does not inspire any confidence. Consumer apps that focus on Enterprise and are only interested in SaaS revenue almost always follow the same path of endlessly degrading the user experience once they reach a certain point. I haven't seen anything that makes me think they will be an exception, but I give them credit for actually having a real support channel, at least as of a few years ago.

Can you expand more on the Screen Time issue?

Might be outweighed by the bigger effects when they do screw something up. Like if their passwords mess up for amazon.com, some big airline, Facebook, etc... the noise will get pretty loud pretty quick.

This is exactly why I use 1Password and not the manager in Chrome, and I won't use Apple Passwords either.