Sadly, developers love to share-in on that hitlers megalomania and obsession with panthers, tigers and KTs, so whole community has to pretend that WW2 didn't started before 1942.
Are you not fed up of getting the exact same thing, game to game, when there is a whole fucking LOT of interesting and unused generally in games armor?
Have you played MoW series? Steel Division? It is possible to make an interesting WW2 RTS without shoehorning muh wunderwaffe krupp stahl.
I'd love to have new units. But when your problem is the timeframe of the games, why complain about Panthers specifically?!