As a medic:
Treating allies and earning xp with kit in hand is great!
But dropping the large medical kit on the ground (you carry 2) without gaining xp when the allies use it to heal themselves is less cool... So there's "no point" in dropping one on the ground...
(By the way, have you seen many on the ground during your games? Nope for me).
Please ! Add gaining XP whan allies uses the medikit when we drop it on the ground ! 😄
Without tell too silly, I think it's the same thing with support class ammo boxes: do you gain xp when an ally uses the ammo box when you drop it on the ground ? I'm not sure I have play all time medic and one or two times support without notice if i gain or not XP.