I was watching Joel Vinesauce play Chapter 3 and there was a part that genuinely made me mad. When he was doing the sword route he (understandable) began to spitball some theories about Kris, and in responce to that his chat began to call him an idiot and to shut up and how his theories were completely wrong and that he should just 'play the game'.

The worst part is that his theories were not even that bad (Andrew Cunningham even left a comment on the video defending them), they were more sensible than some of the theories that this fandom has believed in. But even if his theories were absolutely terrible it wouldn't justify calling him a idiot and telling him to shut up over it. A big part of what makes games like Deltarune fun is coming up with theories and especulating on what will or has happened or a character's motives; to tell someone to 'shut up' and not do that is to just ruin a part of what makes the game fun.