While some areas that allow trophy hunting charge steep fees that help conservation, I can't see that I've ever seen an accounting of it being at sustainable levels. And the proof is in the pudding, where in Africa, rhinos, elephants, giraffes, cheetahs, and many more are declining rapidly.
I'd say that if someone really wants to hunt, they should not be selling licenses to hunt game, but to hunt poachers, something that can fight back (policies are already shoot on sight in many areas). Donate, get deputized, go hunting. We only have a few years before many key species are gone forever.
It's really a question of the extent to which humans get bothered when prey populations get too big and then they leave the preserve and start getting hit by cars. Or too many wolves and they start killing farmers' sheep. Culling helps avoid the wild swings in population.
I'd also point out that even with populations that are not in good shape (threatened or declining), selling super expensive hunting licenses can still make sense. If $50,000 = +3 rhinos, let the hunter kill the rhino. Of course there are perverse incentives and all sorts of practical difficulties, but I just want to make the point that it's possible for that sort of thing to be in the best interests of the species being conserved.
Part of the problem is that the [-1 rhino] is a guaranteed figure, and may increase, but [+3 rhino] is speculative, requiring many steps that may go wrong, from mating, fertilization, gestation, birthing, survival to adulthood; bird in the hand vs bird in the bush. It may turn out that the number is more like $1.5 million for a license than $50k, which already seems outrageous.
I also have close family who work directly with African wildlife foundations and although I've heard much discussion of solutions, I've never heard any mention of this as being viable.