1) Much more so than Star Wars.The original version of TOS is still extremely available. (To the extreme!)
2) Someone says "I want to watch this Star Trek thing you keep going on about. But I hear there are different versions. You tell me to watch the originals. How do I do that?" And you have to answer "Um. Go buy the Blu ray sets."
In olden times that would be not only reasonable but even obvious. But nowadays for MOST people (certainly casual viewers) what's "available" is what the streamers serve up. Or what gets aired. Neither of which is the originals.