In what way would Google profit from restricting 3rd party launchers? I can see why Twitter and Reddit want to charge access for 3rd party apps. Profit. Lots of profit. I don't see where Google would have anything to gain from restricting a very significant customization option in Android.
F-Droid
F-Droid is an installable catalogue of FOSS (Free and Open Source Software) applications for the Android platform. The client makes it easy to browse, install, and keep track of updates on your device.
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They have been diminishing 3rd party launchers with various updates already. Multitasking gestures broke various things and didn't work well with third party launchers - I think the animations still don't work. The toolbar they added for foldables and tablets only works with the built in launcher. The last one sucks because Samsung made one for the Fold prior to that which was launcher agnostic (was better too imo).
That said, things are still pretty great and it's one thing I hope they never kill off as it allows a crazy amount of customization and personalization. Without it, fuck me might as well get an Apple (well maybe not).