He’s not even that famous in the UK IMO
I worked at a concert venue in London for years and McFly played a few dates there about a decade ago. The fans were outside the stage door every night they played, which used to happen a lot but they were a particularly vocal bunch. One of the days my boss was signing out at stage door and she could hear from inside that there were girls crowding the door, so she turned to the guy waiting behind her, rolled her eyes and said something along the lines of “They’re so annoying.” The guy laughed, she turned to leave and then said to him “I don’t even really know any of their songs”. He said something along the lines of “They’re alright, you know.”
Anyway she got home and looked them up and the guy she’d unwittingly spoken to was Tom