Thanks for the testings. In my opinion this makes the whole situation even more broke. Just imagine getting snared out of nowhere.
You still need one squad with LoS on the vehicle to do it.
Tbh I'm not sure is this possible to fix, it may be an animation bug with the panzerfaust and USF AT grenade.
If it is possible to fix I'd lean towards removing the LoS check from all snares rather than adding it to SOV and UKF. The cancelling snares still allow you to target them when they can't actually be thrown so they feel unresponsive.
Doesn't the same apply to US LMGs and PPsh 41 too?
No.
The USF BAR, OST G43 and OKW STG are the only weapon upgrades I can think of which are absolute improvements: the other weapon upgrades make the squad worse in some respect. LMG upgrades make squads trash close up and don't fire on the move, SMG upgrades make squads trash at range.