Borg doesn't have a Windows version, for example. Borg is also command line only, while Duplicati has a nice graphical UI - by running a web server on localhost.
I've been using Vorta as a GUI for Borg for a while for personal use. It's not the prettiest thing out there but it has seemed to work fine so far. As far as restoring from old backup goes, though, I've only really tried that with a few individual files.
Windows still seems to be unsupported.