Yes, that'd be correct, but on a superficial level, it also helps anywhere else. But imo, say you're practicing a job out. You might want to run it through dungeons either for gear/leveling purposes or ex primals. The parser under these conditions would help you to start tunning your rotation in order to achieve a decent level of profiency. Same with sitting in a training dummy. You don't want to learn your job during raid, that's for sure.
It's a guide, extra data never hurts. Now if people DEMAND certain degree of DPS, well, that's up to them. Right off the top of my head "skip soar or disband", you can filter the poor performers instead of trashing the whole group because one or more people. If people are farming primals, they want to do it the fastest way possible and that requires players that are good. inb4 people interpret this as "OMG PURFFFECT PLAY AGAIN YOU ELITIST". No *SLAPS* NO! "Good" as in "people that got their rotation down" and "know how to play their job" and "are not dead weight for the group", like the DPS on the OP's fflogs: Both the tanks and the healers were carrying the DPS in that group, do you think that's fair? but you already covered that when you spoke about its utility in raid content. However, I am sure this also happens in Ex trials, which you excluded.
The tool can be used completely or partially, depending on the content you're running. It's always amusing to measure your own performance and comparte it to the rest of the group. For better or worse, it's there.