

Quantum was popular as “oh god, our cryptography will die, what are we going to do”. Now post-quantum cryptography exists and it doesn’t seem to be clear what else quantum computers are useful for, other than PR.
Blockchain was popular when the supply of cryptocurrencies was kinda small, now there’s too many of them. And also its actually useful applications require having offline power to make decisions. Go on, tell politicians in any country that you want electoral system exposed and blockchain-based to avoid falsifications. LOL. They are not stupid. If you have a safe electoral system, you can do with much more direct democracy. Except blockchain seems a bit of an overkill for it.
3D printing is still kinda cool, except it’s just one tool among others. It’s widely used to prototype combat drones and their ammunition. The future is here, you just don’t see it.
Cloud - well, bandwidths allowed for it and it’s good for companies, so they advertised it. Except even in the richest countries Internet connectivity is not a given, and at some point wow-effect is defeated by convenience. It’s just less convenient to use cloud stuff, except for things which don’t make sense without cloud stuff. Like temporary collaboration on a shared document.
“AI” - they’ve ran out of stupid things to do with computers, so they are now promising the ultimate stupid thing. They don’t want smart things, smart things are smart because they change the world, killing monopolies and oligopolies along the way.
#1 is like tactical nuke tech available for all civilians, #2 would make sense if all the production line and consumers are in space too, #3 would make sense as part of the same.
Earth gravity well is a bitch. We live in it. Sending stuff up is expensive, sending stuff down is stupid when it’s needed up there, but without some critical complete piece of civilization to send up at once, you’ll have to send stuff up all the time.
It’s too expensive and the profits are transcendent, as in “ideological achievement and because we can”. Also they may eventually start sending nukes down.
Thus it all makes sense only when we can build and equip an autonomous colony to send at once. Self-reliant with the condition that they will get needed materials from wherever they are sent.
I suggest something with gravity though. Europa or Ganymede or Enceladus. Something like that.