Mass tourism protesters squirt water at Barcelona tourists 2 years ago
All the waiters and tour guides can't just re-train as semi-conductor technicians.
Even given time, it's not obvious that Barcelona or Spain has the necessary pre-conditions to be globally competitive in another industry that would bring in the same amount of dollars per capita.
It's an extremely ambitious, all-hands-on-deck type of national undertaking to shoehorn your way into something. Japan did it with auto-manufacturing in the 30s. East Asia in general with high tech manufacturing.