Start up New Vegas. Look around you. See that open world? That's Obsidian's attempt at replicating what Bethesda does best, but their attempt failed. Nobody is upset because they didn't copy every little thing from a Bethesda game, Bethesda fans are unsatisfied because of one single thing, and that's the boring world Obsidian created.
You old school fans are pleased because it's a better RPG than Fallout 3, it has a better story, better quests, more fleshed out factions, and so on. I'm not arguing with you about that. But the fact is that the biggest thing they failed at was creating the open world that Bethesda fans love. If New Vegas was the same as it was now, but Bethesda had been in charge of creating the world, Bethesda fans would have been just as happy as you old school fans are.
Here's a good place to start, mate... coming from an 'old school' fan.
First off, take a step back. These are bitter, angry people... and they have a -reasonable- explanation for it. They've had more than a -decade- of disappointment... and for many of them... Fallout 3 just bastardized the whole thing by slapping them in the face with almost NOTHING they could recognize.
I get where you're coming from, too. You're trying to be reasonable.
But for the majority of 'Old School' fans... reasonability isn't going to come for some, long while. If ever. That's just what happens... and it's a sad thing.
If you really want to help them, refuse to argue with them.
Don't debate things. Don't respond to their endless arguments and outrage at your opinion, if they show it. Why? Because they can't help it... not any more than I can help it when I blow up at someone for saying something I find to be profoundly stupid. It's not right, and you shouldn't let us get under your skin.
Just voice your opinion to those willing to hear it, and understand it, and appreciate it.
Nobody else matters. Its your right to have it. Even if I think it's dumb. (Which I'm not saying I do.)