An interesting interview in yesterday's Times (behind a paywall).  He comes across as a very pleasant & level-headed young man, who is clearly unimpressed with Nick Kyrgios ( ):

Ruud is mild-mannered on and off the court, but has attracted the ire of Nick Kyrgios, in a feud that began after their match at the 2019 Italian Open. Kyrgios forfeited the deciding set after throwing a tantrum, prompting Ruud to brand the Australian "an idiot on the court". Kyrgios retaliated, tweeting that he would "rather watch paint dry then watch [Ruud] play tennis, boring".

"I try not to waste my energy on being negative or showing frustration, because in this game it's only about a couple points here and there in many matches," Ruud says now. "I would rather my energy be fully focused on those most important points. Some people might think it's boring and that's fine, they don't need to watch me. I know I don't have the big flashy game with tweeners [when a player hits the ball between their legs] and the drop shots. [But] that's the way I prefer to play the game. It is good to have different types of players, it brings excitement. A lot of people love watching [Kyrgios] and other players that show emotions, then you have Federer, or Bjorn Borg back in the day, who are very quiet. I guess people enjoy watching them too. I'm more on the cold and calm side."

He's the 12th seed at Wimbledon.