You claim that you want solutions for:
> - The lack of an easy way to know what all programs on your phone are exactly doing;
> - Sensible application permissions. (I just want to share 1 photo but somehow the application has access to my entire disk/folder?)
Yet when Graphene (and Flatpak etc) locks everything down and makes dangerous permissions opt-in it's also a problem:
> Projects like Grapheme seem to just lock down the software completely and make it unusable for all kinds of use cases
If you want per file permissions that can also be implemented with tools that exist today. For the photo example I usually just copy the image rather than uploading from disk, clipboard access however is another security issue.
What would a solution you can accept look like? I agree a fresh OS would be nice but there are solutions to every problem you mention. Even old hardware without binaries are possible for the truly paranoid. It's not perfect but you have to be pragmatic.
I think I've made my point that free software didn't really fail. Is it perfect? Absolutely not, but neither was electricity in the 1800s or even today. Did electricity fail?