This is LITERALLY the reason why the Devs didn’t separate them. There is a blue post and everything saying they hope this keeps lower level BGs active.
Continuing the discussion from XP gains from PvP in Wrath Classic:
Separating Ques will have only a negative effect. We been down that road before. No reason to ruin Wrath Classic and a core part of the game which is Twinking.
This is true, they aren’t there to PvP which is why they complain. The solution is simple if you plan to BG just go to the AH and buy some gear. Get some enchants, but flask maybe scrolls, some pots. Then work on professions as you are leveling. That is called playing the game.
If you Que for a low level BG with gear you haven’t upgraded, enchanted and have no professions. You are skipping the part called playing the game because you think that starts at max level for some reason.