I think you will find that David Pleasance was one of the true leaders of Commodore. He had the only profitable arm of Commodore, from memory and was working from a massively limited budget so of course he was going to big up the product that was selling rather than say that the Amiga needed to go in a different direction. It would be commercial suicide to state anything other than "our current product is where we need to be with development into newer products in the future".
Commodore UK didn't kill the Amiga. The parent company was fully responsible.