Because many important apps (banking and other financial services, major shopping sites, most Authenticators ) don’t provide open source versions, I don’t see how this thing can end up be practical for daily usage. Maybe it can be useful for criminals, underground hackers, but not a normal person.
Many of us don't want banks or shopping sites on our phones.
AndOTP authenticator works great for me. I also wrote one that I use on an offline computer (TOTP is rfc6238) in case my phone dies or is unavailable for some reason.
My only gripe with my current usage of GrapheneOS is that sometimes when the notification bell goes off and I open the phone, the SMS was sent many minutes ago (up to an hour or so). I'm only presuming it's due to a lack of google services or something about GrapheneOS; but it might be the network operator.
Using a FOSS OS does not require the user to exclusively use FOSS apps on the OS. Compatibility layers, emulation, and virtualization improve the selection of apps on FOSS platforms before native alternatives become available.
Yes, the most convenient way to install most proprietary apps on Android using a FOSS client is through Aurora Store, a frontend for the Google Play Store: https://auroraoss.com/download/AuroraStore/
The utility of these platforms depends upon what you use your phone for rather than some amateurish classification of people.
Personally, I have never tied myself down to particular apps. What I use tends to be fairly generic and doesn't compel me to use a particular implementation by a particular company. I suspect a great number of people are like that. While my case is due to a lack of interest in the latest fads and an interest in open technologies, someone else may do so for security and privacy, while others may be interested in investing their energy in pursuits other than gadgets.
As important as technology is to the functioning of modern society, I think there is a tendency to forget that some technologies have very little lasting impact.
