In teamgames it is. You don't have to worry about not having snaring squads or sth and your infantry can always be supported by werfers/stukas. Most of the 3v3 games I've played. Volks and grens usually get upgraded to Obers and PGrens (which once vetted shred any and all allied mainline infantry).
Only scaling for USF is through bars/zooks.
Brits the same.
Soviets through 7th man which uses all weapon slots.
Provide me with the argument for the "horribly wrong". If it's so obvious, surely you can argument it easily
What do you even mean by scaling, by your logic the only scaling for Grenadier is MG42 ?
If we look at pure bonuses from veterancy, USF and SOV mainlines are scaling way way WAY better than their axis counterparts and Infantry Sections build on to an insane base value.
And finally, if Grens and Volks are being "upgraded" to Obers and PGrens, so are Concripts to Guards and Shocks, Infantry Sections to Bren Commandos and Rifleman to Paras and Rangers.
If we look at weapons, both UKF and USF can field double guns on their units, which combined with better "veterancy bonus" infantry makes them basically elite infantry. And yes, in team games USF infantry is supported too with its SOV allys Katyusha or UKF Off-map barage.