The first mistake was not tossing the application after "Yes, I'm the best". If this is the vibe he's putting out at a time when first impressions are being made, not sure why you'd expect anything different later. This played out very unsurprisingly for me (though I gotta say, I haven't seen that level of negging from a candidate before). Perhaps there are shades of Nigerian scams here: "if they eat up my original ridiculous message, I bet I can get away with more."
