I am a human. My account is older than the time OpenAI decided to make ChatGPT available to the public.
After I wrote my last post, I remembered that the sentence «How many sets do you have left?» probably isn't just used as a form of small-talk among "bros", but in the context of gyms, where there is a limited amount of exercise machines, it is used as a way to ask when such a machine is going to be free again. Now it makes a lot more sense why the poster in the image said that and why the other people would react that way.
But never been in a gym. I am guessing asking about the seats is likely some sort of gym joke or something. I really don't know why he asked such an odd question.
(I live rural, we get our exercise out of doors here)
He said "sets". I assume that in gym parlance that's how you ask how many more repititions they are going to do before they leave it free. Whenever I've been in a gym I just wait until they fuck off.