The original Diamond and Pearl had a Multi Battle mode in the Battle Tower, where you could team up with an NPC against 2 other NPCs. Why did the remakes (BDSP) remove this feature? I know the easy answer is "because they were lazy", but I don't buy this. I think there must have been an actual reason for removing it.

One reason I've heard online is because BDSP actually increased the difficulty of the Battle Tower a lot, compared to previous Battle Towers, so maybe an NPC Multi Battle partner would just be too much to deal with? What do you guys think?

I also want to point out that SwSh had already removed the Multi Battle mode before BDSP did it.