If you want to stop Shell FCs from being a thing, go to the root of the problem. Don't punish FCs that are only three friends enjoying the game together.

Workshop access should be available to ALL. Not just FCs.
Everyone should be allowed to access airships and submarines.
Everyone should be allowed to access projects.
Everyone should be allowed to have a communal chest for extra storage.
Everyone should be allowed to access gardening, with indoor growing plots for apartments.

Most people don't care about housing. They care about the Workshop/Airships/Submarines being gated by housing.

Don't blame the players for fixing the system where SE denies us stuff.
And before you say "join an FC", that is meaningless. Every FC I have ever seen gates their members so that only the officers and leader get to access Voyages and Projects. Not the general membership. So that isn't a solution either.