Franco, being the same horrible dictator that killed a lot of innocent people, favoured actively Catalonia's economy over other provinces, for decades.
Is true that he discouraged them to speak in Catalonian language, but also discouraged people to speak in Galician language (and Franco was born in Galicia). At the same time give them priority in the efforts to rebuild industry and infraestructures after the civil war. Catalonia is richest than other parts of Spain, in part because Franco wanted 1) having a cluster of industries next European frontiers and roads to trade and obtain foreign divises easily, 2) money from tourism 3) conjurate the revolts giving the area a special silk-hand treatment after the first iron years passed.
Specially in the late stages of franquism, a massive exodus of workers from other parts of Spain migrated and stablished in Catalonia atracted by the favourable conditions to work and live and the "smell of freedom".
I'm aware that this counts as black heressy for millions of young people in the area, but well... nobody will stop them to read history books about post-war if they want. Ask your grandpa. Everybody in Spain has an uncle or some cousins in Barcelona.
Oppression is not something allowing you to became one of the more modern and rich places in the country; oppresion, to me, is what happened to Extremadura in the same period for example.