Vet 0 double bren commandos have almost equal max range dps to vet 0 lmg34 obers.
Max vet double bren commandos have around 90% of the max range dps of max vet lmg34 obers.
Commandos brens are a little more than 50% better than infantry section brens (while getting their cover bonuses). Commando brens (and all lmgs that commandos pick up, I believe) can be fired on the move too.
Again, I know the values, but that's beside the point.
The point is an argument with unrealistic setup was used.
Do you know anyone playing multiplayer who regularly uses BRENs on commandos, isn't 4v4 player and have at the very worst rank 300?
Literally no one does that, because its not efficient muni use and it doesn't suit commandos role.