It was meant to be while he was at Coventry I think. Being flash with money on a night out and a general twat to people is the rumour - ‘My shoes are worth more than your outfit’ is a quote widely attributed to him on Reddit. Obviously a completely unverified source though.
I found it a surprising one because, as mentioned, Maddison comes across really well in interviews but I guess a lot of young guys would become egomaniacs on a night out if they were suddenly earning thousands of pounds a week. Then they’d mature into a more reasonable person as they calmed down and got older. Maybe that’s what’s happened with him.
Think he definitely has a future as a pundit given how articulate and comfortable he is as a speaker.