This is essentially another artifact of the same underlying issue as in T186035: because we merge Wikibase’s autocomment and the content of the edit (e. g. the new label, description or alias) into the comment text, if I mention a user name in an alias, MediaWiki renders it like a link –
– and Echo sends a notification as if I’d been pinged on a discussion page:
The same thing also happens if the user name is mentioned in a string value. I imagine other value types are also affected.