Perhaps the ENTERPRISE-D superstructure was preassembled on the ground for ease of guarantying everything fit properly and then was disassembled into smaller sections for transport to the drydock in space. Much easier to do the preliminary work without having to worry about a lack of atmosphere if something goes wrong. (also don't have to worry about several hundred workers having to do it in spacesuits)
Since the shot of the Galaxy class parts on the surface of Mars was technically in an alternate universe, it could be hand waved away as not being the case in the prime universe, if someone really wanted.
Tangential perhaps, but do you know Park My Spaceship? I checked the Enterprise-D against Apple's headquarters and honestly it's not too far off...
I wish they would go back to using physical models instead of CGI. But I know that will never happen.
Doesn't the TM have a line about an initial six ships constructed and an additional six spaceframes being stored for future use? Could be what we're seeing here.
You know the sad thing? I've seen more realistic looking CGI ships here on this board (and around the internet) than some of what we get in various TV shows (ST among others). Shows like ST are always getting behind because of post-production work and they're always saying it costs so much to do those effects. Yet some on-line CGI artists are doing equal or better work at home. It's crazy.
It's a matter of time and resources. Fans can afford time to tinker and rerig and such. Not saying there isn't a way to streamline the process but I have no doubt that there is. Just that studios and the freelance artists they hire are not operating the same as fans.
It does say that, yes, but in the context of the episode Geordi uses the holodeck to recreate the laboratory in which the Enterprise-D's engines were designed (specifically the warp core, based on the graphics on the set and all the dialogue about power generation, modifying the the dilithium articulation, and aligning the matter and antimatter streams). When he first enters the simulation Geordi looks out the window at the Galaxy-class ship outside, in which we can see welding flares flickering amongst the exposed framework, and muses "right back where it all started". The strong implication is that the ship is the Enterprise herself, still under construction.
Never say never... The Orville did that. Traditional physical models and motion control cameras, augmented with lashings of modern CGI of course, to deliberately evoke the glory days of 90s Trek. One might say the best of both worlds.
TNG, DS9, VOY and ENT all had the same warp effect. It was standardised for almost 20 years. Now we have Discovery not even having the same warp effect between individual seasons