It's conceivable that after some time someone could have rebooted it in much the same way Chris Carter rebooted (in a sense) The Night Stalker into The X-Files. The Night Stalker was cool overall, but inconsistent in its only season--certainly it wasn't anywhere near as consistent as Star Trek's first (or second) season.
I would not use
Kolchak: The Night Stalker as a reference, as it was already a highly successful concept before the watered down series (one record-breaking TV movie & a sequel almost as potent). So, for Kolchak, it was a case of a starting high, then sinking as it moved forward. That is the opposite of a series which failed in its lone season, and required rediscovery / reboot to give it a life it did not earn the 1st time around (ex.
Firefly).
It wouldn't have become a phenomenon if there had only been one season. There wouldn't have been enough episodes for much of a life in syndication, and you wouldn't have The Making of Star Trek, Star Trek Lives!, The World of Star Trek, or anything like that. And without those books, and especially without the long life in syndication, you probably wouldn't have Star Trek conventions, either.
That is a very important point; 1960s sci-fi was on shaky ground for most of the decade--if it failed, it was forgotten as quickly as one turns off a light.
On that note, if TOS went the way of
The Time Tunnel, those all-important, semi-academic, but fan encouraging books would not exist (would a 1960s publisher care about a single season series the audience did not support?), which lends much weight to your point about TOS' chances of "living" to see another day. Moreover, without TMOST being a reflection of the interest in a continuing series, I also doubt the early interest in adapting TOS as an animated series happens at all--thus another major anchor for ST as a thriving property would be lost.
As wonderful & powerful season 1 was, there's no reason to think studios of the 70s were going to explore bringing it back in any form--animation,
Phase II, or a big screen production. At best, it would have shared the same fate as
The Time Tunnel or the
Planet of the Apes TV series in the early 1980s: episodes edited together to make TV "movies" for the weekly programming / marathon blocks.