No access to Shadowlands quests

I had leveled my main to 80 renown in a covenant recently, but never really finished any of the campaigns. I then went to my lvl 70 mage to find that I can’t access any Shadowlands quests at all. There are literally no quest givers anywhere. Ideally I would like to skip the intro leveling story and choose a covenant immediately, but I’m not able to do that. Why did Blizzard remove the Thread quest after level 70? Why would we want to go back through the leveling quest on an alt when we’re level 70? Shouldn’t it be the opposite? Someone help me out here because the way they have this set up now is essentially removing an entire expansion for me. I can’t find any quest anywhere to even progress the leveling quests on my 70, it makes 0 sense.