Are Tommies bluntly superior to everything with bolster+2x brens? No they arent, they are very strong but they arent superior. In early game they can be punished just as bad as rifles if you didn't play it right, thats why whole UKF early game is handled by UC\rec.team call in, yet, its still completely possible to play full inf sections openings, its just harder.
x2 Bar rifles are perform perfectly fine at close\mid range, which sometimes could be the problem on open maps, but as I said you have m1919 for this situations, and inf company to cover almost every single USF weak spot in teamgames, with an exception of MG\AT gun choice.
Because they want to play USF, without wanting to accept how faction works and how its supposed to be played, therefore relying on cheesing, the same way Ostheer heroes abused pre-nerfed 5-men squads, with the exact same fucking argument that "Grenadiers suck ass, because reason X makes 4 men squads non-viable, therefor the only way to play ostheer is 5 men squads".
In other words, its just the easiest way to play USF right now and the hardest one for enemy to counter, plain and simple.
UKF!=USF
x2Bar rifles are performing poorly atm since its a late game setup and knowing you're always facing elite infantry spam from OKW that outperform riflemen and how gren vet3 are simply OP and perfectly stand their ground vs them.
Players aren't doing Path because they're stronger, Path aren't any stronger than riflemen statwise so your comparison with 5men gren doesn't make any sense here. Path provide an edge which is vision and good long range stat but if you give USF a real stock option to get vision range early game (other than being forced to build a M20, like give RE 42 sight range as pio) and you'll see path strat drop.
I've been playing more than 20 2vs2 games this week-end and 80% of which with at least 1 OKW players had overwatch selected, and if it wasn't Overwatch, pfuss or JLI. Ostheer side, Scope everywhere.
You can't come here and say how boring is it to face Path and at the same time spaming JLI/Pfuss or Scope or reco loiter + Lefh, every single game.
I've been almost exclusively using Infantry doc myself so those 40/60 players who insta picked their long vision range doctrine can't really argue they did it because of Path.
Riflemen are bad, Path being overly used is just a consequences of bad gameplay decisions made by the modding team when they decided to give free vision range to everyone except USF (and then decided that it wasn't fair so the Major could get it as well lolol@trolltheplayers)
Talking about M1919, let me tell you it is a mew upgrade. Here again you would expect to win Gren but that's not really the case and vs OKW elite infantry roaming everywhere well you're not going to contest any JLI/Obers/Falls/Pfuss on the field with them.
Now I use them because even being bad, for their cost and being techfree they're better investment than BARs.