You still get suppressed with oorah popped. Keep your MG supported so it has more vision, and positioned well so that a sqaud can't get into its frontal arc unseen. This way there'll be no way to rush it frontally. If he flanks use your supporting squad to fight them on the approach.
You can't dump an MG down and be done with it, or put a squad in green cover and look somewhere else. You need to put as much effort into actively microing your defence as your opponent is putting into their attack.
With vehicles just reverse away. Familiarise yourself with the range needed for the snare and stay well out of it. Oorah is easy to predict, easy to spot, and easy to dodge with a tank.
