I never suggested that they did. It doesn't even take careful reading of my statements to understand I'm talking about manufacturing components on the ground and assembling them in orbit. Just like the ISS. Just like Roddenberry and company proposed back in 1966.
Unless we see the whole thing being lifed off from the ground in one piece, just assume the assembly seen in the trailer scene was part of a systems test before its broken down into sections and shipped into orbit to be finalized and made spaceworthy.
The big problem with building it in space is that its easier for people to work without spacesuits and with gravity that they're used to. More people are going to be qualified for ground-based construction than work in a space dock. Build as much of it on the ground as you can.
I think we're close to agreement now. My only objection is that a popular trope in harder SF
and space opera (although suspiciously lacking in Trek), is that of the "spacer"; a seasoned, lives-life-a-millimeter-from-death worker whose means of earning a living involves almost constant exposure to weightlessness and vacuum. They survive because experience has taught them that every move is considered before executed. Such a character would likely argue that working in space is perfectly safe ... for those who pay attention to their actions.
But as I say, there are few spacers to be found in Trek. I think Mayweather was the first potential such character, but we never saw him exercise much expertise. I credit that to unimaginative writers who probably lacked familiarity with the possibilities his character presented. Add to that Matt Jefferies' belief that all repairs should be able to be done in a pressurized, shirt-sleeve environment, and a picture begins to emerge of a society that fears space as much as it works in it.
Now don't point at that and start crowing. That's more of an uncanonical extrapolation than saying the
Enterprise should be built in space, but it's worth considering.