I don't see how Hardcore encourages looking down on regular players, that's why there are 2 separate sets of achievements. I love the way Hardcore makes you play the game like you had to play it 30 years ago, without save states. Me enjoying the frustration doesn't mean I also look down on other players.
When it comes to supported regions in RA, some games work different in different regions (more work for the developer) and by default most PAL games run in 50hz, making so that they literally run slower than an NTSC copy, making them not very enjoyable to play and potentially making it unfairly easier to get competitive high scores in RA. Thus I can see how for many developers it isn't worth it to support PAL releases, not many people play those, same with japanese releases, they're not very popular.
With Doom of course it would obviously be an option to toggle on or off. Achievements + saving i guess would be a problem in a way so I guess there should also be a normal and a separate Hardcore set of achievements, the other not tampering with saving at all and the other maybe only allowing saving only at certain points or maybe not at all. Doing it like this should avoid the "is saving bad?" discussion, you could play both ways.