No, there's 2 kinds of platforms:
the weapons platforms you add to guardians squads, these are a part of the squad and don't take any additional choices on the force org chart (it's like a marine with a missile launcher - he doesn't take up a heavy slot when he's in a regui;ar squad, the platform is just another way to carry the weapon into battle)
the support weapons listed in the heavy support section do take a heavy slot and can't join a guardian squad, though the crew are guardians
