@darth Yes sir, USA born and bred. I don't know how widespead WhatsApp is used within the United States, but I've heard its considered the go-to messenger app for overseas travels.
imessage is very common, as is facebook messenger. I don't actually know anyone who uses Signal or Telegram. The idea that the government/big tech spies on everything we do/say on our devices is so commonplace that no one (or at least very few) seem to care anymore.