Lightroom Classic Export is cropping rather than scaling

I am using Lightroom Classic export to create a new version of an existing image to post on social media. I am prom,pting export to create a new image with a new anme in the same folder. I am specifying the new image should be limited to 1MB, should have 72 DPI from exisiting 300 DPI and the long edge should be 2000 pixels. 

According to Adobe: "Long Edge and Short Edge - Applies the value to the long or short edge of the photo and uses the original aspect ratio of the photo to calculate the other edge."

Thi says to me that it will apply the 2000 pixels limit to the long edge and then calculate the short edge size in order to maintain the current aspect ratio. I wanmt to do this to scale the image down to a smaller size for social media. What it is doing is cropping the photo in the process which I do not want it to do. 

The original image is 12848x7200. The image created by the export is 9157x7185. The original imaghe has an aspect ratio of 1.78 while the exported image has an aspect ratio of 1.27?! In addition to this the export actually crops the sides of the original photo. 

Is this a new bug in LRC?

[moved from bugs to discussions according to community rules - Mod.]