While I haven't exactly moved from the 2XL to the 2 I do own both. Bought both at launch but since I generally prefer a larger display I've pretty much used the 2XL exclusively. In the past week I've started to use the 2 some.
The smaller body and lighter weight are a nice change but for me that's the only positive differences I notice.
I notice less battery life when using the smaller 2 though don't see an issue with getting through a day on a single charge if I need to. But on my 2XL it seems like I can use keep the screen on and use it a ton and not even think about managing usage to have enough battery for the day. On the smaller 2 it feels to me I have to manage heavier usage a bit more if I want to get through the day. But again, I don't feel the smaller 2 has bad battery life but the 2XL definitely has better.
As far as the screens, I prefer my 2XL. Not only does it come down for me that bigger is better when it comes to the screen, I've come to appreciate the longer aspect ratio giving me more screen real estate. I know there has been a ton of talk of "issues" or quality of the 2XL display but I've not had any issues or bothered by any of that.
So after handling both, unless I want to use a smaller and lighter phone, I don't have any reasons to not use the 2XL.