Would you rather the boss just stand there? The mechanics weren't very hard, if at all. In fact, it was about the same difficulty as ShB's last MSQ dungeon, and that was arguably harder.

The second boss of Dead Ends wasn't hard IMO. It's all telegraphed well with a fair amount of time to move.

Also it the AoEs happen in a set pattern, so you don't have to "guess". One of them is moving inbetween to a safe spot and the other is a merry-go-round.

100% the dungeon wasn't made with raiders in mind. Because if it were like Savage/Extreme, then wouldn't mind it past the first boss.

I'm not trying to be mean, but the expectation that a boss should just a literal striking dummy, is why there's a rift between casuals and those "raiders" you claim it was made for. If you can't be bothered to pause, think about where you need to stand to dodge said mechanic, then perhaps you need to work on tracking visual indicator and recognizing AoE types.