There's no way to do this in default JIRA, and I believe this is actually by design. Deleting users can cause potential issues in the database, if I'm not mistaken.
Is your concern that these users are taking up user licenses? Really, as long as a user is set as inactive and isn't in a group that allows Application Access (thereby not using up one of your user licenses), you should be fine.
If your concern is that you have a hard time managing so many users, you should be able to filter down to just active users, or at least filter down to users who have a certain Application Access.
As Alex said, don't delete users. Make them inactive. JIRA is a relational database and in the history there is a pointer to the user, not their name, so you'll get an error displaying it. Therefor you lose historical data about who did and said what.
Hey Community mates! Claire here from the Software Product Marketing team. We all know software development changes rapidly, and it's often tough to keep up. But from our research, we've found the h...
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG
You're one step closer to meeting fellow Atlassian users at your local meet up. Learn more about AUGs