Any economist would say both Spaniards and foreigners were factors in that economic disaster.
You said only Spaniards are guilty, and Britons poor victims. I say both contributed to the stupid increase in prices. In fact, UK housing prices are higher than Spanish ones.
I never said Britons are poor victims. Thery are also greedy.
But the Spanish mayors are the ones who surrendered protected land to be built with stupid houses. The lack of legislation and the endemic corruption are the only causes for the wreckage in Spain.
The stupid increase in prices and the nature wreck are different issues. For the first, both foreigners and Spaniards are to blame, for the second only Spaniards are to blame.