Ah I feel I should have worded this better.
I didn't mean that all jobs get such buffs they can toss onto 1-X other people. Rather that some jobs can have "buffer" as their identity in a less homogenized setup, where they deal some of their damage by empowering somebody - or multiple - other people. Like Dancer does with their partner right now, they get another buff on the partner ever 120s in addition to the near-passive one.
But to prevent a situation like we had before where multiple such buffers align their buffs on one or more people who are a burst-type or ramp-up type damage dealer and cause non-linear damage gain, these buffs would be intentionally unable to keep synced with the burst window, to a degree where using them more often is better than aligning them.
That is, burst-type damage dealers get their burst window every 120s. Like now. The CD happens to be that. But the buffers no longer have 120s on their buffs, and those buffs are also very rare and only on jobs whose totaly DPS is something like 60% personal / 40% buffs or so. True damage dealers, but only dealing barely over half the damage themselves. hence they need to toss out those buffs on-CD (keeping them misaligned with the burst job's burst window!) lest the total damage loss becomes very bigly very quickly.
I would not foresee many such jobs though. Dancer would definitely need to be one. Incredibly small but near-permanent effects can also work, basically current-bard, as their own damage can cleanly be scaled down to compensate and as the buffs are just-about-passive, all types of damage profiles gain equally from it.