stop reading all you want, that doesnt change that its true.
every faction has internal balance as well as external balance. this exactly why RE got made worse, as internally they were more cost efficient than rifles.
take panthers as an example of how internal balance works:
both axis faction have one. if you added a doctrinal panther with 4 levels of vet to both factions, identical in every way, for ost this panther would be more expensive than their stock panther, for OKW it would be cheaper. the EXACT same unit, in different factions, would have a different cost efficiency
conscripts in OST would be broken powerful, pgrens in soviet with the clowncar would be devastating.
pios cant be directly compared with RE because they do different jobs in different factions. there is overlap, but ultimately, they are completely different units. at no pint can pios be an AT squad, this needs tro be considered. when pios build a bunker, they dont get riflenades for sitting inside it. this has to be considered.
RE are lite rifles than trade combat power for utility. they get a lot of utility AND retain USF flexibility. pios are defensive engineer units. they are different units, filling different roles, in different factions. this is undisputable fact, weather you elect to read it or not.
I don't really think what you say is anything of value.
What you spend a wall of text explaining is that basically not every faction works symmetrically against/with each other. That's something we all know. And in the older days, that was even more exaggerated.
To the point: you say nothing by pointing out that if OKW had a Panther with 4vet (????) it would have a different cost efficiency. Ofcourse it would have. In the same exact way that if SOV was a science fiction faction and had T51s with 25vets and RPGs as snares it would have a different "cost efficiency".
However we try to keep the convo at earth level, not science fiction movie level. REs, CEs, Pios, Sturmpios, RE are all considered to be engie units. Just because there is some flavor inbetween them does not mean they are different.
All of them are supporting units, some better at it some worse at it. REs in 2022 balance tend to the worst aspect, because they have been nerfed to oblivion over a course of 6 years. At first they were spammable to shit, then they got nerfed, then they got their cost up and now they are a "not good not bad" unit territory. Basically a USF "Ostruppen" thing.
Pointing out fictional versions of doctrines cannot help. That's my end point here.