Let's run down Support in MW3 vs just plain old Assault UAV
Support: UAV is at
four kills vs three for Assault. Let's say they take the lowest possible streak set.
UAV, CUAV or Vests, SAM Turret - that's 4, 5, 8.
Say an average player hits 20 kills in a match (and I'm being generous here, this was never typical in my experience). That's three UAVs from that player for the entire match, because remember, the streak doesn't reset.
Oh god, the horror! (and the last one would presumably be showing up near the end of the match,
and multiple UAVs at once don't add full duration)
Compare to UAV on Assault, which is 3 kills, and resets each time you die, meaning that if you score 3 or 4 streaks in a match (that's 9 or 12 kills in sequence out of your hypothetical 20), you're getting 3 or 4 UAVs in a match compared to Support.
The other hilariously ironic thing about this, if everyone is running Support with a similar setup,
everyone is running Counter UAV and/or SAM Turrets.
That's totally ignoring that
a) Assassin shuts down UAV, CUAV, and EMP, giving you free reign to destroy full teams of Support radar users and
b) You get a pointstreak point for every UAV you shoot out of the sky and
c) Support is shiny and new, of
course everyone is going to spam the shit out of it, the novelty of not having your streak reset on death is fresh. Expect to see the same for Specialist once players level up a bit.
Ok, you can resume freaking out now
fake edit: There is one semi shitty thing about the UAV spam - multiple UAVs have an upgraded effect, so until the Support spam wears off, you will be in pain until you have Assassin. Sort of the 'oh god, where's my Stinger' of MW2 early levels I guess