This must be a very personal experience as I recognize none of this and never heard this from anyone either. I think you just simply need a newer phone. I have a cheap Samsung and I live in a place where the sun is always on and usually no clouds, and yet I walk kilometers every day doing work on my phone. No issue reading anything. And like the others say: the camera app automatically and very robustly pics up qr codes when you wave it past it.

I like qr codes anyway: I don't like dead tree printing or touching stuff that is not mine but had a million hands on it (I had that before covid).