Yes, paella is really not a 'restaurant' dish. Certainly not for restaurants that have the kind of rotation of covers expected in busy or touristy areas.
It is very much an 'eat where the locals eat' thing.
My top tip for those holidaying in the region in self-catering accommodation is to find a nearby place that does them to order, and book to pick up at your chosen time.
One of the few cases where 'takeaway' is often more reliable, better quality and a more enjoyable experience than dining at a restaurant.