I was thinking the same thing when walking by and "viewing" the things they had at my nearby grocery store. I saw the older versions, up to 140lbs. I recall I bought the Huggies pullups when in my late 20s. The GoodNites.
I think I saw another version competitor. Maybe pampers(?) I dunno.
I did think, as I stood in the aisle yesterday; that they were calibrated for a small body where the main absorbant pad is the same for many adult diapers, but without the extra useless fluff that is needed to fill a regular adult diaper in the back. I don't know why the fluff in the back is so awfully useless.
My assumption was, as I recalled how much they held...at least back when I bought them...that the focus was to help a sleeping smaller body, no matter what position. There is no need for back fluffing.
I tried using a booster in all sorts of places within the adult diaper to copy the concept for the horizontal-mode Goodnites and others did, and find boosters can actually impede comfort. But that's another conundrum. The boosters help, but kinda do weird things, like push and distort the fit which seems to inhibit wearing them without ironic odd leaks, etc. I swear, I think a booster is best for a wide crotched-diaper, with a long front and back to make it work, along with good inner guards " ".
Sorry to get kinda off the subject