It’s something I’ve noticed too. Average Taiwanese people have a strong Chinese-American accent, and uses a lot expressions like “Oh my goshhhh” that make me vomit, but they can’t make a single complete sentence. They also use words or expressions that you know that come from a book for sure, like “toast”. Any slice of sandwich bread is a “toast”, no matter if it’s toasted or not. Every single Taiwanese calls it that way! Obviously the saw a draw of a toast in some book, and they memorized the word, not giving even one minute to think what’s the logic behind. S
o as I see it, they don’t use English, the repeat English words and expressions, that’s all.
PS: the “toast” thing drives me nuts!