Pentagram, I differ on this point: do think it is good game design to (usually) move the end of a long chain from solo quests into a group dungeon or raid. It makes sense to turn up the intensity for the last act, the face-off with the Big Bad.
You do make a decent point about different types of content, though. I remember the salt flowed purple when the Cloak required BG wins in Pandaria - and they weren’t even RBGs. 
All the zone quest chains culminate in a dungeon in BfA, as they did in Legion.
However, BfA professions do not require dungeons to skill up, except Herbalism Anchor Weed Rank 2, so you can safely resume those without being forced into dungeons.
I understand your reluctance to waste your time on “impatient angry people”, though my observation is that only about 10% of runs involve some grief of that kind. I do know a couple of people who are quite affected by it, though, and therefore avoid it. By the best figures I can glean from public statistics, you are not alone: 15%-30% of players avoid random groups to some significant degree.
You could, though, look for other people who also don’t like the uncooperative and abusive mess that groups sometimes devolve into.
This community, for example, is for people like you:
While I’ve noted that such groups tend to be not very active, and you won’t instantly get a group in any of them at any hour of the day or night, if you stick with it and ask for others a few times, you WILL end up getting a friendly and patient group to do your quests with who have the same mindset you do.
Don’t give up on dungeons entirely. They’re actually fun! as long as you’re with a group who have the same objectives as you. Just gather a loose network of friends and contacts you can get through them with comfortably. It’s a pity that Blizzard doesn’t incentivise this kind of play, but at least Communities do partly enable them.