Seriously 3-5 minute repop on NMs?

[Betelgeuzah]

I have explained that it's about scarcity. To some people, the rarity of these fights is part of the appeal.

And that rarity can be achieved through other means- like making the encounter so difficult that it can't be done without proper preparation and even then there's a good chance you won't win. And if you win, you are one of the few that get to do so.

That is much healthier way to promote rarity.