This issue was discussed on the Discourse Meta forum:
- https://meta.discourse.org/t/why-do-permalinks-include-my-username/19901
- https://meta.discourse.org/t/disable-u-user-in-shared-links/25356
- https://meta.discourse.org/t/unencrypted-usernames-in-shared-links-break-anonymity/42554
- https://meta.discourse.org/t/twitter-shared-url-has-a-query-string/47446
- https://meta.discourse.org/t/why-do-all-shared-links-include-the-username-u-username/60126
- https://meta.discourse.org/t/share-a-link-for-a-post-should-not-leak-username/66489
The co-founders didn't seem to think it was a problem.