Yes... no offense to Dream Team. If you don't like James' voice, fair enough. People here have mentioned Gillan. I've never quite loved Gillan's voice. It's just not my cup of tea. To me, he was fine in his prime, but really hard for me to listen to after that. If people feel that way about James, that's fine.
But it's just frustrating to see, again and again, very baseless judgments on what James is "doing wrong" as a singer, and even more baseless comparisons to singers that really are nothing like him.
I am barely passable when it comes to music theory, but even I can sit down at the piano and play the melody to "Number of the Beast" or "The Trooper", and then play any number of James melodies, and hear how much more complex it is in terms of using more notes and range, more complicated timing/syncopation, key changes, and so on. That is why I think that you simply can not use what Bruce does as a rationale for why you feel James should sound a certain way at his age. What the two men are doing, even on their latest albums, is very different, and always has been.