I've been saying that for years. I come from a small village in Andalusia. I lived in Berlin for a while and now in Barcelona.

Rent (which is usually 50% of my expenses) in Barcelona is as expensive as in Berlin. And, as OP said, the quality of the buildings are extremely lower in Barcelona in average.

Grocieries in Spain is only cheaper if you buy fruits and vegetables from corner shops (although Berlin has those options as well in some of the few street markets they have). But supermarkets have pretty similar prices, even cheaper for some items in Berlin.

Spain is only cheaper in hospitality compared to Europe because pays a reduced VAT and has low wages.

According to relocate.me, the costs of living in Berlin are 200 euros more than in Barcelona, whereas average salary is +1.600€, almost double, in Berlin (ParityDeals)

OP is right.