It's a complete mystery to me why certain YouTubers do this. I'll take the worst human voice (even Fran Drescher or Rich Evans) over a synthesized one, particularly for expository narration. It reminds me of phishing phone calls, and instantly draws me away from the actual content.
You take back your disparaging comments against the sweet wonderful voice of Rich Evans. His angelic laugh is soothing enough to stop babies from crying.