Why do the dimensions automatically scale up when saving out now?

This has only begun happening with a newer version, but lately when I am saving out files and checking the "Use Artboard" option, when I go to the actual file, it has scaled up drastically. 

So, if I save the file on an artboard that is 1080x1920, the actual file is 2250x4000 and 2MB.

WHY DOES IT DO THIS?! Never was a problem until the past month or so and is completely inefficient and annoying to deal with when I have to resized EVERY. SINGLE. FILE.