Grow taller is not a controversial goal and growth can be resumed because previous knowledge of growth plate was flawed.
Why there isn't a startup which can resume skeletal growth.
So there isn't several billion dollar in funding to such a problem which huge proportion of people suffer from?
You can raise billions of dollars from general public alone if you promise you can develop such drug or treatment in a decade.
Aside from that, the amount of people who are willing to take the side effects of growing is not going to be that large. I think most short cisgender men aren't actually insecure enough about it to take medication for their height. Then you're going to have to develop therapy to make sure that people are able to deal with the psychological aspect of continuing to feel insecure despite improvements in appearance, like they do with extreme weight loss or plastic surgery.
If someone did successfully create a product to increase height, it would create a lot of people who realize they are insecure about everything else after they get taller lol