You might not think that trivial content like roulettes is worth being annoyed over, and that is your prerogative, but that is the premise of this entire thread. It's undeniable that our AoE capabilities have taken a hit in most roulette content (the vast majority of which is below level 70); spread shot got nerfed from 100 to 80 potency, and bishop got given the flare treatment with damage falloff.
The other more important change, and the one that makes me wonder how you can say 'rotationally nothing changed' is that we lost lead shot. We lost an entire element of decision making to do with AoE, which was deciding when to stop multidotting things with lead shot in order to start AoEing proper with spread/grenado shot. Pulls often take some time to set up before the tank finds a comfortable spot to stop in, and lead shot gave us a way to use that dead time to pre-dot everything with lead shot, so the whole group was ticking with that juicy 480 potency's worth of damage before you even began to AoE. Even for pulls where combat proper begins immediately, you still had to do the math in your head whether investing a GCD on lead shot was worth the tradeoff compared to the more immediate payoff of spread/grenado shot.
Now, losing that depth to the gameplay is one thing, but it also represents another hefty nerf to our damage throughput, as lead shot used to be one of the highest potency/GCD and potency/TP skills in the game by far. Multidotting is so strong that you should feel the loss of that damage output very acutely across the entire spectrum of downsynced content.
I agree with you that at level 70 in dungeon-type content, machinist AoE isn't all that bad. While we are no longer as good at multidotting many separated targets as bards, our burst AoE on clumped targets is still somewhat decent in short timeframes (ricochet got a buff too which helped). But as the title of the thread says, it's below-70 content the OP is mainly talking about and I agree with him that it is a miserable experience with our current toolkit.