Why wasn't Portugese the common man's tongue in Goa like it was in several other colonies?

Even after 450 years of colonization, Konkani and Marathi were dominant in Goa, why is that? One reason I've heard is Brahmin Christians demanding monopoly over the language inexchange for conversion but considering how insanely repressed Konkani and Marathi was, you'd expect it to die out by 1900s. Can someone give me other reasons and sources.