Yep, and DPS units have their own stat checks to deal with too. Basically, raw power in itself can make a unit a lot more versatile. For example, Soma is fine when you're a newbie but she'll never be good at cracking through 400+ armor units thanks to her silver stats and lack of an attack modifier. By contrast Spica can eventually hit 1k+ damage per shot and that makes her a viable option against a much wider array of targets.
The problem is that tanking is very binary and that makes Gellius a problematic template for what the class should look like. You can either take the hit or you can't, and since Gellius style heavy armors can do literally nothing else but act as a door stop their only virtue lies in surviving things that other classes can't. That's troublesome because Aigis war has enough different tanky units now that "Gellius style or GTFO" hits me as an even worse option than letting heavies stagnate. It'll grind some people's gears, but the patched SAW Deine/Diina model where Heavies do more than just take haymakers to the face is probably the better way forward than making heavies even more turtle-y. Personally, my big hope is that the HA Second Awakening has some pretty dramatic options that really mess around with their stats because as it stands now I feel like heavies get overcharged for the ability to quad block. A heavy armor build option that "only" blocks 2 or 3 but is cheaper and/or can wreck some face would make me, Miranda and Garrett a lot happier than just tacking on moar armor and moar block.