We can't speak for all teens, gay or otherwise. They are not all the same mind. The degree of sexual activity and relationships among teens would range from zero to highly active. They are not all concentrated in the highly active segment.
"Grindr" services are commercial. Inherently promoting, advertising, "luring" target customers with a wide net. That would mean luring all segments of teenagers, if Roth's idea was realized. It's gross.
If some teens already use those services, parents and educators of the teens, and the services should do more to keep them away. Roth's "embrace" idea says more about his personal angle than consideration of teens in general and their families.
I see that Penn State removed access to Roth's paper. Nobody seemed to care. But it should be made available because free speech means we record bad ideas, discuss why they're bad, avoid them in future, or evolve them to better ideas.