well, i read the first few posts and i don't agree. I think what happened
was that there was one organization which we can think of as more or less replacing NASA. But for a few years, you'd expect to see things still labeled
with the NASA tag out of habit and inertia. But after a while NASA is a totally replaced agency. Then the same thing. I mean "probe agency"? Should say it all don't you think? Probes are unmanned craft. Starfleet at first probably starts out as a division of that agency, then overtakes it, and finally replaces
I think whats going on is slow transitions between agencies and joint agency ventures while that transition is happening.
However, i don't really have any proof- thats just always been my supposition.