Pete is a reclusive nerd who, while good at what he does, often can't see outside his own bubble and kicks people down when they don't see it the same way. His comment was still not correct but if he's focused on one single element of the Who's history and Live at Leeds was a big show for the time, it's easy for him to pick out small moments at that time and claim they influenced the metal musicians that came after him. I still think using the word 'invent' was either a deliberate bastard move to make people talk, or it was his way of reminding people the band were around smashing guitars, playing loud and being rebellious before metal arrived. I'm sure he knows he didn't invent metal, just like he knows that suggesting he influenced many metal musicians wouldn't be talked about as much