Most vehicles with dual-filament bulbs will turn off the low beams while the high beams are on, but looking around, I see it's mixed for vehicles with dual bulbs; US standards don't require it one way or the other --- you can meet the high beam requirement with separate bulbs or with both bulbs in concert.

I think complaints about headlights really started when different bulb types came out. HID, projector, and LED bulbs all cast qualitatively different light than the ubiquitous tungsten halogen bulbs that preceded them. A lot of these put out a lot of blue, especially in the fringes that I find very objectionable, and the lumen output seems to have increased quite a bit, as well as the spread.

Halogen bulbs were tightly constrained by power limits and output requirements; but the other types can hit the output requirements at well under the power limits, so they can cast a wider field of view (which is nice), but may need to be brighter in more of the the wider field of view to hit the output requirements in the central portion, and that additional brightness is more likely to cause glare. Of course, all of our eyes have aged as well which makes night vision more difficult, especially with light variance. I remember my parents sometimes complaining about other vehicle's lights when I was young and thought everything was fine, but everyone was using halogen lights back then.