STD makes some sense because it acknowledges the Star Trek in the title but when you think about it is also the only one that would. TOS, TNG, DS9, Voyager and Enterprise don't. What is also interesting about Voyager and Enterprise is I feel they use their acronyms the least and also funny was their use to be a big deal about Star Trek not being in the name of the show but nowdays most people just call it Enterprise instead of Star Trek: Enterprise anyways.
I never called it "Star Trek: Discovery", I call it "Discovery" or, yes, "Disco". The "Star Trek" part is understood, so it doesn't need to be said.
As far as IRL, I don't talk about
Enterprise at all. I never did even when it was on. The only Star Trek show that usually comes up among most of my friends is TNG. The few times it's not TNG, it's usually TOS. That comes with the territory of being in your 40s.
IRL, I call them:
TOS --> "Star Trek" or "The original Star Trek"
TNG --> "Star Trek", "Star Trek: The Next Generation", or "Next Gen"
DS9 --> "DS9" or "Deep Space Nine"
VOY --> "Voyager"
DSC --> "Discovery" or "Disco"
PIC --> "Picard"
I
only use "Star Trek" in the name for TOS and TNG. That's the way it's always been. On a subconscious level, maybe it's out of respect for the fact that both were created by Gene Roddenberry and the rest are just spin-offs created by other people, regardless of whatever I think of them, good or bad.
So even if you try to make the use of "STD" sound more palatable, it doesn't work. I'll say what I always say: when I see people call
Voyager "STV" or
Enterprise "STE",
then maybe I'll begin to take that argument seriously. Until then, no dice.