I prefer 1080p but if not available then 720p is perfectly fine as well. 4k is overkill and I don’t even have a monitor that could play it at native resolution. Where I do prefer “lower quality” though is framerate. I don’t like how 60fps looks so I force YouTube to play videos at 24fps.
That’s not at all obvious to me. I think recommendation algorithms are much more likely to provide you content you dont agree with than you’re to search for it yourself.