On tiktok its basically for views....if u post vids which r trending and will get more views ppl r more than happy to do it. And since most ppl know that once u get good views this can be a good source of money, so evry1 keeps hoping that their vid will get more views n profile becomes popular.
Now coming to 2nd point, most women not just in India but globally also r nt aware that lift n carry is something which comes naturally to them. If a women is healthy and has no injuries, they can easily lift sum1 whos 10-20 kgs heavier than them in most of the lifts, same goes for guys too. Earlier very few women would try this, bt now since its becoming part of challenges n dare women r lapping it up. Coz rarely u ll find a women who would want to be looked down. And in this case, where there r so many vids, evn they get motivated atleast to attempt it
And be it man or woman evry1 likes to show off a bit and also loves it when they know that they r actually stronger than what they think, so now when suddenly they r able to lift their bf,hubbies most of them take a liking towards it. In my personal exp, evry time I got a lift or was around a lift happening, 1st reaction of women doing it was realization n excitement that they can also lift their partners.