Because the only mobile OS provider which allows blinding tracking frameworks with a single click is Apple currently, and every software vendor will want its telemetry and ads for their "monies".
The application model evolved from "pay this to get that" to "train this AI implicitly which we gonna use against you, and ah, we also sell your every aspect of you" to see cute cat GIFs.
Some of us are seriously against this and Android doesn't provide that. Maybe it's because Google is an advertisement company which provides nice looking (free-ish) utilities which also acts as nice data funnels (incl. Android).
Also, we have a gatekeeper called Google Play Services. In other words, even if you have a custom ROM, you need that all-encompassing framework to have nice things.
Clients may differ, but the cloud platform and the connector which enables all these "Android" things is closed source, and controlled by Google.
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If you want to install microG super easy and are still choosing your next phone, get one supported by LineageOS: https://wiki.lineageos.org/devices/
Then instead of the official LineageOS build, get one from here with microG preinstalled: https://download.lineage.microg.org/
For low budget folks, a lot of Xiaomi phones are supported. You'll have to sign up for their account and wait for a few days, but otherwise the process is pretty straightforward. E. g. this is for my current phone: https://wiki.lineageos.org/devices/ginkgo/install
Lets not forget the stuff you (and most of us) so loathe is direction Apple is actively heading for few years via their own ad-space. Truly surreal discussion.
Seriously, basically any other topic we can discuss like adults here but when it comes to Apple and their restrictions/bad behavior it feels like the most upvoted posts are paid ones (not stating they are, but it certainly would look like that on more generic forums)