I guess my only question is what then happens when you want to disable the Google Play Store and Google Play Services. Mind you, anybody who uses custom ROMs and such likely does not sign into the Google accounts anyway, so would not be able to download a third-party app store from the Google Play Store because they refuse to sign in. And Google Play requires sign in.
Yea that’s exactly it, no more side loading needed.
I guess my only question is what then happens when you want to disable the Google Play Store and Google Play Services. Mind you, anybody who uses custom ROMs and such likely does not sign into the Google accounts anyway, so would not be able to download a third-party app store from the Google Play Store because they refuse to sign in. And Google Play requires sign in.
Nothing different. You download the F-Droid APK and install it just like you do today.