When the tickets are only €25 it’s not just for the rich. The opera house is a cultural landmark, preserving it serves the public. And it was 1.5B spread over several years, not all at once.
Honestly, the ‘money on art bad’ argument is not a good line here.
The cost was spread over several years. And at 25€ a ticket this doesn’t just serve the elite. The building is also a cultural landmark, so preserving it is of social interest, and the money spent went straight back into the local economy, where it was swiftly taxed again.
These arguments are lazy, find better ones.