Earlier quoted context omitted.
I don't get why high fat foods are lumped in here. I've started avoiding all the others you mentioned, and my reflux has stopped, but I'm on a ketogenic diet that's very high in fat.
Some foods loosen the sphincter making it easier to get reflux. Like eating a slice of pepperoni pizza. My dietitian said each individual is different so you need to determine what works or doesn't works for you.
I think the most effective dietary advice in the world is this:
Change one thing for two weeks, and see if it gets better or worse.
You can fix a surprisingly wide range of problems by changing your diet in a slow, methodical way.