This is a question for the closed issue https://community.atlassian.com/forums/Jira-questions/Required-scopes-and-permissions-for-rest-api-3-issue/qaq-p/3135981#M1179779
Was there a recent regression on this problem? It looks like tokens with scopes and basic auth stopped working somewhere between April 25th and today.
My scoped token was created on April 9th and worked at least until April 25th.
If I use a new token without scopes, I can retrieve issues again..
The answer from Gor on the linked issue indicates that scoped tokens are supposed to work with basic auth!?