I agree with the OP. A laugh is a natural human reaction to something funny. It isn't necessarily voluntary and is a pretty open sign that somebody found something amusing. Now if somebody were to not laugh but instead say "I'm laughing" when I told a joke I'd be pretty certain there was no genuine amusement being had. The same goes for saying lol. It's used online to convey that you are laughing because without a camera or mic nobody can tell if you're laughing or not. To say it in person is just plain autistic. So emotionally removed from the scenario you may as well be on the other end of an internet tube.