At least the Spanish integrated local folk beliefs into Catholicism instead of erasing them and calling out those beliefs as sacrilege and satanic to enforce compliance with the empire. I'm glad that I grew up with siestas and not a Calvinist work ethic that permeates and persists in today's hustle culture.
Christianity as a whole has tons of Pagan traditions carried forward, so I wouldn't give the Spanish that much credit. If you want foreign people to adopt your religion you incorporate their practices into yours.
That caring how the city's name is spoken/written is just a dog whistle for people who want to be exclusive to feel special. It's not like they're trying to get the name right because they really care about the saints. They just want to feel like they belong more than others, because it makes them feel like they have a stronger identity. But it's just a word for a place; we all get what 'San Fran' means. Getting uppity about is just performative insecurity, like grammar nazis.
Frisco has been said for a long time by black San Franciscans (of which there are currently so few there is literally a movie called the last black man in San Francisco). Cringe if you want but there is history behind calling SF Frisco in certain communities.