There should not be a "View Wiki" link on project pages. This would refer to Phriction (Phabricator's wiki), except we have this disabled. This may be an upstream bug.
See https://phabricator.wikimedia.org/tag/collaboration-team/ and screenshot.
The link takes you to an explanation of how Phriction's behavior has changed, but since we don't have Phriction, it's confusing. Project pages that want to can simply link their wiki in the project description (in fact, that's what the message advises).