I think once the FC Uniforms were introduced, they decided Class B would become the more formal look than Class A. Definitely by the time Ross and Daugherty were wearing them.
Personally, in the World According to Sciā¢, the First Contact uniforms would be it. They'd be the only standard duty uniforms and they'd still be wearing them in 2399. Also, kids these days should get off my lawn...! Anyway, I'm not sure what the point is of so many different designs is. I thought the point of a uniform was to look, well, uniform. But whatever, it's not a big deal either. And I'm very much looking forward to Lower Decks!
There is no William Decker. There's Matt Decker and Willard Decker. And that quote was from Matt Decker.
Yep that's my brain fart I confused/combined William Windom - and the character he played Matt Decker. My bad I'm old.
Basically this. Its not really canon until it is. But it does give a nice backstory to those that are interested in one.
The answer is no. No they are not. Not even close. However, they're entertaining and that's what matters. To quote DC comics' about their Elseworlds: It's an imaginary story but aren't they all?