True.
I think the key point is that non-technical site admins look for a fix to get their site working when it’s broken. A “Safe mode” is often perceived to do that (rightly or wrongly). Perhaps a way to do this would be to have additional admin safe-mode controls.
You could add a big button in the /admin/plugins route to automatically disable all plugins in the same way, however I wonder whether it would have the same effect. Perhaps it would.
I’m also drawn to this as it’s quite doable within the current Discourse plugin architecture.