Yep, the at-will damage of a Rogue exceeds that of the Hex-enhanced EB+AB spamming Warlock.
As it should be.
EB+AB spamming warlock as a baseline is a good choice. They shouldn't be high damage, because they have invocations and spells to fall back on.
The longsword+shield fighter in plate shouldn't be baseline damage, because it is intentionally built defensively. Possibly its ability to defend allies should be higher than it is (imo). The other problem is how easy it is to boost its damage output (take PAM, swap sword for spear) (while the warlock's EB+AB+Hex is far more difficult) which doesn't make it a very "stable" baseline.
Warlock EB+AB+Hex is not a tricky bit of charop. It is something most people can see as a way to be ok at dealing damage playing a single-classed PC. And it isn't one build choice away from having its damage boosted by 50%.
The sword-and-board LS fighter isn't far off the EB warlock either.
16 at level 1, 18 at level 4, 20 at level 8. Fighter takes a feat at level 6.
+1 rod/weapon at level 5, +2 at level 11, +3 at level 17.
1: 9 vs 9.5
2: 12 vs 9.5
4: 13 vs 10.5
5: 26 vs 23
8: 28 vs 25
11: 42 vs 40.5
17: 56 vs 43.5
20: 56 vs 58
These numbers are really close. The fact that magic weapons add +1 damage, while implements do not, makes a difference here.
Add in PAM at level 6, no reaction attack ever:
1: 9 vs 9.5
2: 12 vs 9.5
4: 13 vs 10.5
5: 26 vs 23
6: 26 vs 30.5
8: 28 vs 33.5
11: 42 vs 49
17: 56 vs 53
20: 56 vs 67.5
The reaction attack adds another 10-13 DPR on top of that if it always goes off.
But this analysis is both more complex and more fiddly than "use warlock EB+AB+Hex" as baseline damage.
The warlock damage curve is simple, not that extreme, and is in a class that can do more than just do damage. It is a decent baseline.
Treating characters dealing less than it as "not doing much damage" is reasonable. And the conclusion, that at level 11+ monks don't do much damage without expending Ki, and even that doesn't keep up, is useful information.