TNG suggested kids in elementary school were learning calculus but honestly I'm not sure that's a reasonable thing developmentally. Just because the technology improves doesn't mean humans get smarter faster. The cadets here are college students, and generally speaking, pretty competent ones. (God, college kids were dumb everywhere I went to school.) Also technical talent and emotional development are separate topics. I'm also not sure I agree technical understanding has to continue to grow with technology.
Computing technology is much further today than it was twenty years ago, but kids these days understand less about them because the technology is abstracted away better. (People use iPads now with no idea how a file system works.) In the 32nd century stuff feels magical, a lot of people probably don't need to know how it works to use it.
Floating nacelles make plenty of sense if they're independent drive units with all necessary components in the nacelle, consider they create a warp bubble around the entire assembly, but you can obviously wirelessly control a separate structure and the ships can manipulate them with force fields and such. Think about how many times a ship in earlier shows scraped a nacelle and exploded, separation is good design if technology now allows it. And remember... this is like many hundreds of years after Starfleet had timeships that could beam a person to and from any place in space and time. If anything the technology in this series feels a bit not magical enough for the time period.
Yes, I understand that you have ways to convince yourself that Academy is a good Star Trek show. I'm old at this point, and, for me, it's bad.