m4ri0g ADB is not intended to be used on production devices. I'd definitely not advise allowing any app access to ADB. It's not the same as root, but doing so still gives an app way more access than any app should ever need.
I saw the articles about apps not working and popups telling users to install apps from Google Play. If this becomes a big problem, we may advise people to work around that some other way, but the project isn't likely to ever advise anyone to use anything like Shizuku.
Also, see that the apps are still working as OP said here:
Oggyo they do not enforce Play Integrity and just work fine once installed (by Aurora, see below). E.g. - some banking apps, Netflix, etc.
I'd say installing using Aurora is not ideal, but is definitely not the worst way to install these kinds of apps considering they don't show up on Google Play. Some may be in AppVerifier's database, so if you can, verify they're the legit versions that way.