We have to realize that the seed of all this discord is that Star Wars isn't sci-fi, and has zero real respect for technical coherence. Even Ghostbusters or Back to the Future have more sci-fi elements than Star Wars. It's space fantasy. The TIEs have fantasy engines and fantasy fuselage that makes them move like that, with fantasy weapons that shoot like that.
As soon as we try to bind those ships to technical sci-fi specs, everything falls apart.
While I absolutely agree with your overall point, I would argue that science fiction and space fantasy are synonymous.
I understand your desire to differentiate the two, but sci-fi has never actually HAD to try and justify itself scientifically. Some works do, some don't, but it's all still science fiction.
Edited by DarthEnderX