My “kinda new to me” Pixel 4a (I know its EOL and not new) is the fastest phone I currently have.
I run GrapheneOS on it, based on Android 13 with latest updates.
But also it has a hardened Kernel and Malloc, which may be the problem here.
In comparison: A Nokia 7+ with unofficial LineageOS based off Android 13. And a Google Nexus 5 or so, with some very old Android 8 or so.
OpenCamera works perfectly well on both the non GrapheneOS phones? But on my pixel, it loads extremely slowly, like 10s at least. Its pretty unusable.
OpenCamera is a weird project, I can imagine this is a memory overflow or something, so the hardened Malloc is the problem.
OpenCamera only has a SourceForge repo which is very weird. Do you use it and have an idea why this is happening?
He could also disable internet access to the Google camera and use it on his main profile