That's entirely true. I worked in Manhattan in the late 80s and early 90s. There were cell phones but they were large and bulky. If someone was talking down the sidewalk you could see the large phone they were talking into. Now with tiny phones and Bluetooth earpieces it's impossible to know who is talking on the phone vs. talking to demons in their head.
Used to be able to tell who was talking out loud to themselves, crazy or not.
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