This will partially be down to confirmation bias though.

All the posts seem to suggest only BOE panels have dead pixels, so only people with BOE panels are going to heavily scrutinize theirs.

People will check which panel they have, and if it’s Samsung the majority will just go “Phew, okay, I haven’t noticed anything yet either” and carry on. People with BOE will assume the worst and look at each individual sub-pixel.

At least one model of iPhone has even had two completely different modem chips you could get. It’s not valve cheaping out, it’s them having to order from multiple suppliers to meet demand.