I could've been far more brutal than that
why on earth he bothered to share the game and he stripped out things? We are not in 1996 where you had to diminish size to save time and money due to low connection speed.
In any case, I followed your suggestion and I sent him a mail and yt pvt. I removed public message. I have to say for my experience A LOT of people doesn't care or they even don't discover when someone sent 'em private messages on youtube. I found some of them in the past in my channel and YT didn't bother to notice me about their presence.