Maybe because quality doesn't matter to me as much?
And, movies this old in 4k HDR, that's a thing? I can understand the 4k part, that at least can be done by scanning the original film at a higher resolution, but HDR? Doesn't it need to be shot in HDR to begin with?
From my experience due to DHT there are actually more seeders than listed on the site. I didn't have any trouble getting even quite obscure films.