I'm like you in that I only ever buy 13" ultralight laptops. But there are diminishing returns after about 3lbs.
Like yeah, going from 2.8 to 2lbs is great and all but it's not as notable as the jump 10 years ago from the 5lbs bricks to the original MacBook Air. The computer still takes up about the same space in my bag and I wouldn't really notice ~1 lbs difference, especially if I still have to carry around a 1lbs power adapter because the thin battery lasts less than 8-10 hours of moderate use.
In the meantime, the design compromises to get to 2lbs are becoming increasingly aggravating: thinner keyboards that jam, screens bonded to glass so that repair is impossible, RAM and SSD soldered onto the board, batteries broken up into pieces so that replacement is annoying or impossible, passively cooled Intel chips that throttle, weak integrated GPUs. And probably a bunch of other stuff.