But Letterman jackets that look exactly like 20th/21st century Letterman jacket 1100 years from now?
Artistic license, like people speaking comprehensible English, moody lighting, the UT fixing people's lip movements, etc.
I don't believe that they literally are wearing Letterman jackets. The events in Trek are canon, but not the actual visual depiction. Unless you think rocks went through a paper mache period in the TOS era.
