But where is the harm with the bigger trackpad? What issues do you experience? Accidental inputs might happen somewhat more frequently but the palm rejection generally does a good job of preventing them, so what other problems are there with a trackpad of this size?
One of the main issues I've always had with trackpads the size of the ones in the pre-2016 MBPs are that you don't have an awful lot of space to move your fingers around and quickly hit the edges when dragging something around or just moving the cursor from one end of the screen to another, forcing you to release your finger and continue its movement at another part of the trackpad. I'm not saying that it makes these sort of trackpads unusuable or anything, but having the edges get in the way of your finger-movement and gesturing is a nuisance. I know you can turn up mouse movement speed to somewhat counter this, but a faster movement speed doesn't feel very natural to everyone, and you give up a certain amount of precision when doing this.
With the new trackpad sizes, this is pretty much a non-issue, and I think this is one of the main reasons why Apple made the trackpads so large: to simply give you more room for all the 2-, 3- and 4-finger gestures and for moving around stuff without hitting the edges. Your fingers aren't forced into such a crammed space anymore. You don't have to put any thought into where you want to place your finger when you want to drag a file from one end of the screen to another. If you place your fingers roughly at the middle of the trackpad, you're very unlikely to hit the edges during normal mouse movements, which isn't always the case with smaller-sized trackpads.
I guess this makes sense. I have pretty small fingers and honestly i've never had any problems with the size of the trackpad. But i've also seen a lot of people buying the new MBP claiming they'll use it with a regular mouse because they can't stand trackpads (users coming from windows mostly). Won't deny the fact almost every laptop has a crappy trackpad, but that is far from the MBP's and seeing that new customers don't even wanna give it a chance, i don't see why they felt the need to make it so big. Like people who were upgrading from older MBP's were happy with their trackpads, otherwise they wouldn't keep buying or would just get an external mouse.