I'm going to chalk it up to you not knowing about Android, but swapping launchers is basically changing your home menu, it doesn't affect Play Store access and you'll likely need it to buy the Pro version of certain launchers, the most common one being Nova Launcher Prime[0]. And if he did something more drastic, like changing to custom ROMs (akin to OS images), then Play Store access is up to him.
And honestly, I don't think Google free apps and services coming and going will impact app ownership numbers. Android being more popular in low income, developing countries (with big population numbers) will have a bigger impact overall.
[0] https://play.google.com/store/apps/details?id=com.teslacoils...
Android is the number 1 platform in the world. Except in the US, where Apple is manipulating teens using "blue bubbles".
LOL WOW
One of my best friends who was using Allo. Or Duo. Or Hangouts. Or Meet. Or whatever. He really loved one of those apps and it got removed/changed/or something.
My point was that as a developer, I'd want to ensure users like the platform they're on enough to buy my app. This same friend? He moved to some launcher and just uses Discord and Element now. As I understand it, using a launcher prevents you from using the Google Play Store, so you're not buying apps.
EDIT: See also: https://www.theverge.com/2021/6/21/22538240/google-chat-allo...