Well they can promise updates yes. But they are limited on the android version to the manufacturer of the chips. The company shift which has a similar concept as Fairphone currently suffers from that problem: they cannot upgrade their shift5me to a higher version than android 8 and a lot of apps recently dropped their support to older android versions (e.g. banking apps)
This does not only depend on the hardware's lifespan but the software itself too. If there is no longtime support the average user might be better of using a more recent phone where all apps will work and there are not that much security issues.
Thank you for your response! My phone uses Android 8 (saidly the manufacturer doesn't provide the software upgrade...) and at least I did not actively revoke any permissions (as I don't know how :D)
However, your explanation what's actually happening gave me an idea what the problem might be and I found it: I am using Blokada and apparently this interferes with the check. Deactivating Blokada solves the problem and reactivating it will cause the same issues again.
Then I also noticed that my Blokada version is way to old and it didn't received any updates because apparently it was removed from fdroid and there was a lot of fuzz about it which I need to catch up with.
So I guess it's not a jerboa issue. Still, thank you for your help! I really appreciated it.
Well they can promise updates yes. But they are limited on the android version to the manufacturer of the chips. The company shift which has a similar concept as Fairphone currently suffers from that problem: they cannot upgrade their shift5me to a higher version than android 8 and a lot of apps recently dropped their support to older android versions (e.g. banking apps)