This has been bugging me for a while too, so I sat down and hacked out a solution. Adding a single block of code into the /wordpress/wp-links-opml.php file will fix the problem and add descriptions to your OPML files. You can find the solution at my website:
https://ellejohara.com/blog/making-the-wordpress-opml-tool-slightly-more-useful/
Carpe Diem,
ellejohara
