Damn. Been a long time fan. I actually did notice a slight change in the energy of his most recent videos, but I didn't suspect this.
His videos are probably the most scientifically consistent in terms of ballistic testing, which made him very unique compared to the sensational styles of other Youtubers like Demo Ranch, Kentucky Ballistics, or Garand Thumb. If you wanted to know "If ___", "What happens when ___", or "Compared to ___", I would highly recommend his videos.