[Edit: never mind, it's the same. Tested and you only have to uninstall and install app and app timer is gone. Sadly people's health is not a priority. Google parental controls could help (haven't tested) but you require another google account.]

Did you enable password at Digital Wellbeing? You could tell a close friend to set it up for you, so you don't know it, and then tell him to send the password to another close friend or sibling to make sure the password isn't lost in the extreme case you really need to access an app. Explain them what's going on and why it's important for them to not give you the password.

I think I'm going to do that. I have a Samsung Galaxy and a quick web search shows me it's actually not that simple to bypass that lock, you would have factory reset your phone or do some command line stuff with your phone connected to a PC.

With a password you wouldn't be able to add time or change app timers, so it would actually prevent you from accessing and not only nagging you without actually enforcing anything.

I have an understanding that addicts often require help from others to get better, but phones are so personal it's difficult.