Are Enemies Too Aggressive?

Aggressive I support. But I think it's a bit overtuned in its current state, especially at the lower difficulties which are meant to be inclusive of all types of players. Most of the enemies try to swarm you and they've seemingly retained the ME3 trait of no accuracy falloff by range (as well as a very noticeable decrease in the degree to which mobility affects enemy accuracy compared to ME3, see perfectly tracking Observer beams), so you get softened up by enemies closing on you from long or mid range while you're getting surrounded by the exact same units who had spawned x seconds earlier than them at short range. It makes the combat overly one-note and simplistic. ME3 had both negative and positive reasons for mobile gameplay, e.g. kiting Banshees as a negative incentive but also chasing down slow or ranged enemies like Brutes and Ravagers to deplete the wave budget as a positive incentive. MEA has lost some of ME3's complexity and balance in that regard.

I also note the irony of the robot army enemy faction being more concerned with self-preservation than the two organic factions.