So aurora is OS but it's pulling apps from play store. Each time you update your apps the updates will come from google. Unless you will manually download apk files from the web... It works for now but aurora already had issues accessing play store and it may stop working one day.
I have an app for public EV chargers that requires google device registration to work. It's the best network around so sometimes I have to use it. I have device registration disabled normally but that's another example where google services are needed for crucial functionality.
And I've recently installed another app that would not let me authenticate on LOS. Google is doing this on purpose and more and more apps will not work on custom ROMs.
And we are really far away from creating mobile app ecosystem that's not relaying on google. You can install mobian or something but currently absolutely no one supports it. I need android to use my bike GPS, my car charger, connect to my car, access my bank and even to use my climbing wall. None of this has native mobile Linux client. It will take decades before companies start supporting Linux on mobile the way they support it on desktop.
By ethics I don't mean using signal over spying WhatsApp. I mean local shop instead of employee exploiting amazon or mastodon over right wing extremist supporting Twitter. People do understand what amazon and twitter do but not using them is just to much effort for them. Even if it's not that much effort at all...