So part of the coffee shop advice is true. Even if you feel it’s superficial to start. There’s actually a lot to be said for “fake it until you make it” type socialization. Showing up regularly at the same place, be kind to the staff, learn their names, and little by little you’ll find you start recognizing other regulars and the you. It’s okay for connections to start out not super real or deep, it still works those social muscles out. After that it’s just time investment.
The point is this isn’t a quick thing. Go long enough in an environment as a regular and you’ll feel safer and more able to open up.
But if you’re going to argue with the advice provided then why ask?