Not sure why people care so much about there being a plan, the vast majority of cinematic series never had a definite one either.
The difference is that even if its not planned out and something is being created as it goes along, there’s one person there guiding it along.
The OT while not all written strictly by George, was guided by George.
The MCU is being guided by Kevin Feige and they’ve had directors quit because they didn’t want to incorporate elements to setup and support future films.
The ST has no one, each director was left to do whatever they wanted with their entry. Kennedy is a brilliant producer but she doesn’t seem to have a vision for where to take the franchise.
Considering Feige has yet to produce a movie as good as either of the ST films, I’ll take the Kennedy approach.
That said, I still fail to see what the difference is, if one even exists. I don’t know how you could look at, say, the three Thor movies and say there’s one clear vision guiding them.
Feige has a vision for the Marvel franchise, sure, but so does Kennedy with SW. Having a vision for a franchise is more than just about micromanaging what happens in three of your movies.