Always required for indie artists. In certain circumstances it may seem redundant, but it's good habit forming, and does help make it easier for folks to search the artist up.

I try to source it myself and give a big grace period when I see it missing, so no worries. I'm more concerned about those who repeatedly fail to add it after request, or those who god forbid intentionally try to obscure the information.

Note that I still don't see it in the title or post body, which is required. Also for the future, if you do add source links with the name, no X/Twitter.