Kazuki Yao performing Anime Ja Nai ~Yume o Wasureta Furui Chikyūjin yo~ first opening from Mobile Suit Gundam ZZ. Seiyuu Kouhaku Sunrise concert 2021 (no audience event)
grandpa!!! i guess he's as old as Judau does in Crossbone... edit : okay, just checked. Both Judau (in Crossbone) and Kazuki (present day) is about the same age (60s).
Personally I think he's just not a good singer. He currently voices the character Franky in One Piece, who yells even more than Judau did, and Yao does a pretty good job all things considered.