Armored heroes have been a part of the Marvel Universe from the very beginning, when Tony Stark invented the Iron Man armor. While many superheroes rely on powers or just advanced training, armored heroes provide another path: the usage of technology. Relying on their intelligence or their ability to be good pilots, it's possible to go from an innocent bystander to a member of the Avengers.
Source:https://www.cbr.com/marvel-strongest-armored-heroes/