Right. This is all true, and here lies the weakness of the bofors: it requires a big investment in supporting units to be able to hold ground. So much that the brits offensive capabilities are very weak. So how does a player counter this? I will give you a hint: leave the bofors alone and prepare for the long game. Get fuel cashes and tech to panthers and panzerwerfers.
Emplacement play is weak in 1v1. You are simply bunkering down and then you hope that the opponent loses his patience and walks into you. If your opponent decides to do the smart thing and tech rushes, there is nothing you can do to stop him and you will lose in the late game.
As good as this sounds this doesn't happen. If done properly, you keep the opponent away from areas you'd like to set up emplacements on with Vickers and Tommies. Once you force a retreat you are free to put up an emplacement. Leaving a properly placed emplacement alone is not an option, especially on smaller maps where single emplacements are easier able to cover VPs. Not to mention the abundance of maps currently in the map pool that feature plenty of shotblockers which in turn promote campy play; not that there's anything wrong with campy play if that's your thing, but emplacements are simply too cost effective at the moment and shouldn't be dominating the current meta as they are.