I think blizzard just assumed people wouldn’t care.
Like, “no covenant” mage does 7k dps. Dungeon are raid are tuned for this damage level.
Then covenants add 1, 2, 0.5, or 1.7 thousand bonus dps. You’d think you’d choose what you like and be like “yay, bonus damage”. Instead, the community views it as “garbage, standard, garbage, garbage” and now the floor is 9k dps with covenant 2 and 8.9 with covenant 3 is seen as trolling, and it’s downhill from there.
It’s unfortunate, but probably predictable. The lack of tuning that’s happened (and the obvious design faux pas of having one covenant be better on one content than another for a single spec) just exacerbates the issue.