Yes, you can try that. Just not using a Google Account will not be enough though as GAPPS still communicate to the server. You could disable most Google Apps or even try to delete them. That would be Method 3 in this Wiki.
Microg is a FLOSS project that has the goal to substitute many Google Services (all except for anti services like AdMafia or whatever it’s called) and integrate them into the Android System in a way that lets Android and installed Apps believe that it’s Google. (Same Package names …).
@all: I tried Magisk on a fresh Open OS and it didn’t work. Even though I installed the recommended Superuser the Magisk manager kept saying “root not implemented correctly - Android Pay won’t work” (so Pokemon won’t either).
Next I’ll try FP OS, flash Magisk, flash Root, uninstall all GAPPS with Titanium Backup and see if it works then. (Maybe the problem with Open OS is that a different root method is already implemented)