Like Riflemen, Infantry Sections, Panzer Grenadiers and Rangers? There is nothing unusual about this. I don't see how a dedicated anti-tank 4x PTRS penal squad is spam-able. They counter Mediums, Tank Destroyers and Panthers. They'd lose to infantry, and they'd get devastated by Tigers which heavily splash them for large manpower bleed. I'm not asking for anything new, I just want Soviets to have access to the same strategic options that every other faction enjoys: mobile infantry-based AT that works past the first few minutes in the game, and on a unit that is underused and limited in its utility since it's current 2x PTRS upgrade sucks with no scaling.
This is available to riflemen because the whole faction was designed around them.
Ranger and Panzer grenadiers are not mainline infantry and it is difficult to be the core of one's army.
Because then you have a bunch of rigid one-dimensional units that only fill a single or limited role. That's not interesting. There is elegance in quality over quantity.
I guess that is personal preference but I find a combination of units more interesting than a blob of the same units.