Do endgame dungeons feel too long, or am I just brain-rotted?

I'm heal heroics very casually, and I find myself wishing that most of the new 5-mans were maybe 20% shorter. I know it's time to graduate to Mythic 0 for a better challenge, but my impression going in isn't the hottest.

Ofc, my attention span might just be cooked.

What do you guys think about dungeon length?