I think this would only be interesting for a fraction of the user base, a tiny fraction that is. Considering they are low on man power and how they seem to be struggling getting the Nothing Gallery app going, I don’t think they’d free any ressources for such a side gig. Keep in mind that Google-free Nothing OS still needs regular updates and development, they already are at a rather slow update pace every two months.
Replacing Google also isn’t as straight forward: Some third party apps are relying on Google Play Service, if you don’t have Google Play Services, some apps won’t work correctly or not at all. It’s not just about replacing Gmail with a different mail app, Google Calendar with a different calender or Chrome with a different browser and use Fdroid instead of the Play Store.
Huawei was once one of the most popular brands for smartphones here in Germany, but after they were banned from using Google services, their marketshare and sales have fallen like a rock. People realized they can’t easily install some popular apps anymore and this simple issue led them to just a fraction of marketshare left. For Nothing, which is still a small player after all, chasing this as their major path forward could be catastrophic.
Don’t get me wrong, I actually wouldn’t mind an OS like this, but I simply don’t see it happening as Nothing will go either all in or just skip.