One of the biggest "complaints" from anti-Discovery viewers was always to do with "they have holographic technology before it existed!" - to which I always link to this Telstra ad:
Fact is, "back in the day" of classic Trek, stuff like holographic technology was a blip on the radar - practically nonexistant. A twinkle in inventor eyes. Today, however, we've not only established VR (which, honestly could be considered early versions of a holodeck) but also have a very, very rudimentary version of 'holographic' capabilities as Discovery has established.
If Calypso established anything, it was that Discovery ends up without a crew, lost in space for years. Part of me wants to believe that this is because of a huge disaster with the spore drive - a jump gone wrong, if you will, which would explain why the crew had to abandon ship and Discovery ended up alone for hundreds of years. Not implementing the spore drive in any other Starfleet vessel following this incident seems like the most logical conclusion.
The technology is not wrong. It is more in line with how we consider the future.