It's NOT a "straw man " argument!
Again from the SCRIPT AND ONSCREEN DIALOGUE:-
MILITARY AIDE: Bill, are we talking about mothballing the Starfleet?
C in C: I'm sure that our exploration and scientific programs would be unaffected, Captain, but...
The answer is CLEARLY not NO, but is a MAYBE!
Not really, because again, at its foundation Starfleet is a scientific and exploratory program
. His reply is a sideways way of saying they were going to get back to what they were really supposed to be doing and shed the excess built up in response to a threat that would no longer be posed by the Klingons.
At no point was there any reason to think that SF would go away, except in the minds of the characters who can't imagine it as anything but a military force and can't see themselves as anything but warriors. This was the whole source of conflict and development for Kirk and company in the film! While initially sympathetic, by the end of it our heroes see the wrongness of this and work to thwart the efforts of those so obsessed with war that they'd join their own enemies to slaughter their own leaders in order to preserve that way of life. The view that "SF is the military, its officers are soldiers, and that's just the way it is and must always be" is held by the VILLAINS in this movie.