The links to MinervaNeue, https://phabricator.wikimedia.org/project/view/2799/ and https://phabricator.wikimedia.org/tag/minervaneue/, both 404s. However, the project is not struck out or anything that would hint it's restricted.
Oh this is an old bug, the trick is to go to a query URL like https://phabricator.wikimedia.org/project/board/2799/query/LhkyKh0DN2_0/ (where 2799 comes from the /project/view/ URL you posted above, and the query string is any random query string you can get by filtering any other workboard) and saving the filtering as default on the broken workboard. Then you can go to Open Tasks and Save As Default on that. I've done it for this one.