For me the weight in itself is not a problem, just the clamp. The 1990s specifically start hurting my left ear after long enough use. It's like the ear becomes inflamed and actually hurts to touch. The pain goes away in a couple of minutes after removing the headphones. I have a pair of >10 year old DT880s with near zero clamp and those are totally fine. Also DT770s that have a decent amount of clamp but less than the 1990s. I had a bit of discomfort with the DT770, but mostly fixed it by switching pads to 3rd party memory foam sheepskin so ears have more room.
It's weird headphone manufacturers insist on defaulting to so much clamp. If it is necessary for some uses, they should offer looser variants, replacement parts or even an adjustment mechanism.
