There are tools that reduce the amount of blue light emitted from the screen. They essentially turn your screen orange. The difference it makes is large enough that you wonder how you managed before it. The most well known is f.lux, but it's also natively supported in some phone OSes.

Not that long ago, everyone did 1-3 all the time.

Until ~20 years ago "screen time" was at least mostly limited to a (by modern standards) tiny CRT TV on the other side of the room for most people. Glowing screens filling a big part of one's FOV such a large percentage of the day is a fairly recent thing.