I don't understand this idea that Flint's technology requires line of sight. The Federation transporters don't.
Then there's the "conservation" argument—yet STAR TREK features FTL travel and communication and other violations of known physics. Fans readily accept parallel universes, time travel, paradoxes
and phasers that send matter into some unknown realm. So why haul out dogma to deny Flint's demonstrated
technology? (Perhaps the Enterprise
was not "shrunk," but moved away from each of the three spatial dimensions in a "direction" we do not understand yet. Thus, the Enterprise
did not get smaller, but shifted in a type of perspective we do not know.)
Flint is already an enigma. Humans don't simply live for millennia. Granting that is a very big exception to then hold him to other human limitations. But let's give it a whirl. Let's assume Flint's telomeres don't shorten, his blood poisons don't accumulate, or whatever it is that makes other humans age and eventually "run out." Does that mean that mere long life leads to exponential smarts, allowing Flint to single-handedly invent technologies far beyond anything else known in the Federation? (As Da Vinci, he imagined technologies ahead of his time, yet was unable to realize them.) Or did he move out into space along with the rest of humanity, perhaps discreetly picking up bits of alien technology and coupling them with his own creativity into a super-synthesis beyond Federation science—perhaps because shorter-lived humans were wedded to their dogmas that he had long ago learned to live without?