Better than a lot of other methods. What are you protecting, from who and how annoying would it be to recover if it went wrong. I don’t use a password manager because I’d lose the file for sure and it would be just as inconvenient to recover as if someone hacked me. I also don’t have any sensitive stuff. Work on the other hand I have a password manager.

The lowest hanging fruit is using a leaked/hacked/stolen list of accounts/emails and passwords and trying them on other sites. You should be safe from that.

If you have sensitive information someone would be willing to break the law and spend a few thousands of dollars to get you’re not safe.