Playing on that theme some more, exclamation points seem like a fake signal of importance. As in, I didn't bother to take the time to make my message interesti

Playing on that theme some more, exclamation points seem like a fake signal of importance. As in, I didn't bother to take the time to make my message interesting or useful, so I'll add this punctuation at the end to try to trick you into believing it is worthy of your time. But of course you didn't trick them, they just now start to dismiss you. Also, I could see similarities between exclamation use and swearing. Some people swear all the time, so it means essentially nothing. "I like fucking butter on my toast." So they don't have that option to escalate their language in the future. Whereas a person whose previous last use of the f-word was 20 years when they lost their leg in a traffic accident, now says "We need to get this fucking situation sorted out by Friday" gets some extra gravitas.