As I said, it was a mistake not to, but the simple fact is that TAS did not use the TOS themesong.
It used enough familiar elements to be a great "sequel" to the TOS theme. Perfect!
It used Shatner's voiceover, and....?
Nothing else.
Even the opening notes were different, tho' intended to "be in the spirit of", which is always annoying to me. Either do it or don't, but don't try to "be similar to". Why bother? If you like the original so much, why try to ape it? Why not USE it?
I think something from earlier in this thread tells us why. Enough people would pay only slight attention, and really believe it was the same tune as TOS, so they could pass it off AS the original tune.
In the meantime, no need to pay anyone royalties, since the TAS tune was likely done as "work for hire".
This one element comes across as cheapskating.
