There isn't much you can do.

Since MMOs have become more single player games with group content tacked on, and the the advancement of things like dungeon finders, cross realm dungeons, and no travel times, people just aren't valued as anything more than a easily replaceable tool to help you get your loot. That why people only want you if you know the dungeon/raid by heart, and you already have all the loot, they can choose to be picky because you are replaceable. Even tanks and healers face this.

You probably know all this, being a vet, but if I were dead set in finding like minded players to do content with. I'd start by trying to form groups in chat. Thanks to cross realm, you can't really meet people in dungeon groups anymore.You're bound to find a few like minded players than might know others. You may even meet enough to form your own guild.

Or, you could do like I did, accept that MMOs have changed for the worse (for a player like me anyway) and just solo all the time. I really hope that Legion has a lot of the story outside of instances, sick of having to look it up on youtube because the end of the story is locked behind a raid. The raiders don't even care about the lore anyway.