You can choose not to use it at all. My main profile does not and all work fine. Non privacy respecting/ goggle dependent apps I keep in a separate profile.
You can't do that on calyx.
Since play on GOS is toothless , while microG is a hacked up job yea it's better. Microg is ofc amazing , but still a have issues.
Thing is it is very easy to get a signal account with a fake number, I have 3 different ones. My spare phone don't have a sim or number, but do have signal. On my main phone I have one for each profile.