A reliable suppression platform is something all factions have at some stage.
What about reliable AT infantry that UKF and soviets don't have?
What about reliable stock medium tank that soviets don't have?
Reliable light tank that UKF and Ost don't have?
Reliable mortar unit?
Mobile reinforcement?
No, not all factions have reliable suppression platform at some point in the game, just like not all factions have units able to fill the role other factions units fill.
If you're feeling like using feature that faction X have and faction Y doesn't, then play faction X. Players aren't married to the first faction choice.
As OKW you have different means of suppressions, vet4 obers, AA HT, flak truck.
OKW suppression to other armies suppression relation is the same as Ost and USF mines in relation to other armies mines-they aren't better or worse, they are different and you can use it in different circumstances.
Hell, you can even look at CoH1-PE didn't had any HMG team at all and they did fine, they used other units for suppression, they didn't performed as well as HMGs at it, but they had their own perks other armies didn't.
Same thing here.