Speaking from 2s experience only. I feel like the MG42 pio opening vs the USF rifleman opening is actually pretty viable.
The USF player is outnumbered until the officer arrives. Getting a single rifle squad suppressed until that time means you almost lose 1 third of your attacking power. Which kinda makes it hard to win that crucial first engagement to hold down the fuel + cutoff.
Imo another reason why people prefer going paths.
I would argue that your take is true.
USF in general rely very much on early game aggression/pressure to counteract their obvious lack of basic battlefield tools.
On those cases a decent OST player would defend their point well due to MG42. I never argued that.
I argued as to why it's important that pios get vision bonus.