Shadowlands at least had some iconic characters as bosses like Kel'Thuzad, Sylvanas and Anduin. At least we knew them before and they were memorable. But Dragonflight? We have a random Grimtotem in Vault, Echo of Neltharion in Abberus and Smolderon in Amirdrassil - these are the most known characters in all of the DF raids. Like... honestly? The Incarnates fail as major threats as much as Zovaal because we didn't know about them before their expansion. There's neither tension nor interest and Blizzard failed again to build any of that during the respective expansion. That's why Iridikron being the new "Gul'dan" is a good thing and leaves something to expect for the next expansion.