I concur. Apple makes one of the best LCDs around so the display is really good despite the lower resolution. And like you said, the battery life of the XR is excellent.
For me as a moderate to heavy user, the battery life of the XS Max is not “unimpressive”, but totally disappointing That’s why I’m curious to test Apple’s claim that the 11 Pro Max will last 5 hours longer than the XS Max.

If you have the XR, upgrade to the 11 only if you want an ultra wide angle camera and night mode. Else it's pretty much the same phone with a faster processor.