Which is it?
TOS had more of a grand plan or it was better suited to not having one?
TOS was a western in space, that was pretty much the concept summed up right there, TNG was a cold war political commentary in space. Beyond that there was an awful lot of making up as they went along.
I never said that TOS had a grand plan, I said it had more of a plan than Discovery. TOS knew what it wanted to be. Discovery has no idea. As evidenced by another tonal shift for season 3.