They might allow the browser's built in manager. Good chance if they're a Microsoft shill, edge's built in would be better than nothing....although it's Microsoft so a text file might be better.

IT probably bans them because they can't access the data. Keepass files are some kind of container, you can store any file with in it. Great when you want save a txt doc with 2fa recovery codes or something and also not a bad way to send a payload that's impossible to scan. "I'm going on vacation, please use this keypass file for vendor XYZ, open the file within for the vendors contact info".