I'm cynical in general, but this type of stuff always sticks out. "I'm sorry for your loss" from one nameless headless stranger to a different nameless headless stranger feels as sincere as an AI bot, and that's to say it absolutely isn't.

Same as people saying things like "Don't say no one loves you, because I love you <3" but it's in a forum like this, or on Reddit. You don't know them. you don't love them.