I agree that a bad player behind a utility-rich job can be just as bad as a poor selfish-dps. That TA isn't really worth much if it's used all over the place or even not at all.

The main issue with SAM and BLM both, isn't even their literal rdps contribution. SE could buff their pdps so high that it would actually outweigh all the utility other jobs provide, granting them a place in the speedkill meta, but they would still simply be less "fun" to have in your group. It's kind of subjective obviously, but for the majority of players, doing high dps feels good. Big part of enjoyment in raiding is trying to optimize, striving to improve so that you can land those highest percentiles and that simply can't happen if you lack raid buffs other parties have. Of course good players will do well in any composition, but there is always the fact that you could do better if only you had that one buff.