Tbf, Star Trek TOS was also a sci fi show with an FX budget of two shoelaces and a pack of gum, and had to be carrier by great actors and writing, which it absolutely was. It's still my favourite Star Trek to this day.

I think the problem with how the US makes shows is that once something get successful, it gets a budget, which means the writing needs to appeal to a broader audience, which makes the whole thing blander.

I might be ignorant of US television pop culture, but I think, at least before the 90s, the UK produced much more memorable scifi shows (and even in the 90s, a lot of those US shows were secretly Canadian)