See that didn’t make sense to me. Sisko arrived at DS9 in the standard uniform, then changed into the work version. But then Voyager goes out not in the standard but the work version? And once Voyager made contact with the Federation, how hard would it have been to send the new uniform pattern out? They were replicating whole shuttlecraft, with individualized kitsch sci-fi controls even, but they couldn’t uniforms? That might have been an opportunity to boost morale. “Welcome back to the fleet.” But the corporate overlords wanted to maintain the reset button above all.
That said, I didn’t buy that the DS9 uniforms were the work variants. The station was plenty clean after a few days. The Defiant always was. And they switched directly to the carpeted standard FC uniforms, not that uniform’s work variant.
I've always assumed that the season 1-4 uniforms were a roll-out. Perhaps, like is implied in
Discovery, the uniform was rolled-out to new facilities and ships, first. Pike explains that the
TOS style uniform was rolled out to the
Constitution class first. Likewise, being a newly Federation-administered station,
DS9 could have been given the newer uniforms first. Then, ships launched after that could have been issued the uniforms, as in the case with
Voyager. By the time of
Generations the two piece shirt and pants uniform of
TNG seasons 3-7 were being phased out. Starships launched prior to the new uniforms could allow crews to wear either one, whereas Starfleet HQ itself could have been the last hold-out (hence why Sisko is back in the
TNG uniform in "Homefront" and "Paradise Lost.").
Shortly thereafter, in an attempt at uniformity in Starfleet (excuse the pun, but also, don't since it was intentional), the
TNG movie era uniform was instituted fleet-wide to all ships, bases, etc., with the admiralty as the only group with a slower adoption.
In
Voyager's case, it may have been more energy intensive on the replicators to create a whole new uniform style for everyone than it was to upkeep the older style. If you're stranded in a different quadrant, which would you prioritize, replicating shuttles or uniforms? Yes, they were arguably wasteful in the manner that they did it, but that doesn't mean a potentially more demanding new pattern should have been used over general maintenance of the current uniforms.
I'm actually fine with them keeping the pre-movie uniform while they were in the Delta Quadrant, even after contacting Star Fleet and continuing contact on a regular basis. There's the replicator explanation, of course, but changing uniforms was probably not high on their list of priorities.
