A contentious issue for sure. For me I have no problem with the so called high bird shoots providing people attend tooled up correctly and have a good knowledge of what THEY are capable of. On the higher stuff it can indeed be killed pretty consistently with the right gear, and although there will of course be pricked birds (as there are with lower stuff and 30g 6s) I'd like to bet that most of the stuff is cleanly missed as usually it is the shooters skill that runs out of gas before the cartridge if appropriate shot is used.
we all have different comfort zones, there are birds I won't shoot at even when I'm shooting high stuff (so 3/4 choke and 42g 3s Ultramax) as I'm not confident of a kill. As long as people stick to what they know I don't see a problem. Incidentally I know there are plenty that don't, and that is more of the problem.
i don't see shooting the very high stuff as any less sporting than shooting the more local stuff, personally I can't think of anything less interesting than seeing pheasant and partridge lumbering over inside 30 yards (which if people could judge range acurately is the upper limit of most run of the mill shoots) getting poleaxed by a team of guns, irrespective of what choke/load they shoot.
i see the problem more as more of a personal control issue, if you aren't up to high stuff that's fine, practice on clays or take an instructor with on the day to assist. If you are a tidy shot and shooting 2:1 or 3:1 on regular stuff maybe try and try the next level up and see how you go!