The wikidata-bugs list allows people to easily subscribe to all Wikidata related bugs.
The pipermail archives currently have 202k emails archived or about 20% of emails archived in all of Wikimedia's list archives. We don't/didn't archive wikibugs-l and given that all of the emails are just copies of what's already in Phabricator, maintaining a separate archive seems unnecessary. We can also rely on other external archivers like gmane/etc. if people want HTML email archives.
I propose that the list continues to operate as is, but we stop archiving new emails and consider deleting the old archives.