[the-croupier]

It's still early days for my own space opera campaign, but so far I've found GURPS to be more restrictive (in good ways) when it comes to the possibilities of ultra-tech rather than too permissive. That persistent lean toward hard SF that runs through the books can make full-on space opera a challenge sometimes. But it also can make a GM's life easier when it comes to keeping the PCs' power levels from spinning out of control.

Plus, I think a GM is entirely within their rights to simply say a given path of tech never actually progressed in the way we might assume in 2021. In my campaign's future history, yes ships have stardrives, and alien races have force shields, etc. But no, actually, no one ever did figure out how to make an actual, sentient artificial intelligence. Many civilizations tried, and cobbling together something that can completely fool a TL 7 or lower civilization is actually pretty easy. But the genuine article? Never happened.

A couple worldbuilding choices like that will make your campaign more distinctive. When players don't have all the usual options of a genre available to them, that can sometimes take stories in interesting directions. And it can also eliminate kinds of tech that you worry will throw things out of balance. Just make sure you provide a rationale for it.

Plus, eliminating a tech path or two can make a GM's life easier by taking several pages of Ultra-Tech off-the-table and making it easier to focus on the kinds of tech that remain (which will probably still be a very large number!).