The American Idol executive producer, who was responsible for hiring Tyler and Jennifer Lopez as new judges on the reality music show, said that he is "grateful" to the Aerosmith rocker for being himself on the series rather than pretending to be a "tough" guy.
Lythgoe told TV Line: "Steven is the sweetest of souls, for starters. As an artist, he's been through every problem a rock star could go through and come out the other end. He was never tough on anybody [in American Idol], if you look at it.
"When you look at a Top 10 or a Top 13 [contestant] where everyone is really strong in their own right and they've been chosen by these judges, he is never gonna be tough. Not gonna happen. And I'm really grateful for the person he is. Same with Jennifer."
Lythgoe continued: "People said, 'The judges aren't being critical!" I'm not sure what they want them to say. They're not going to turn around and say, 'Pack your suitcase, you're going home.'
"If you're saying, 'I miss Simon Cowell being rude to people,' then that's one thing. But I'd much prefer getting the level of talent we got because the judges were so forgiving in the initial stages, and so wanting the kids to do well, that they kept them and encouraged them through some poor times, and got them to a point where these kids really were extremely talented and growing every week, in my opinion. I prefer that kind of judge at this moment in time with the world."
Earlier this year, Lythgoe praised Tyler for bringing more "warmth" to American Idol. He also said: "It feels like a different programme because it's so different with the personalities that now control the judging."
Watch Steven Tyler performing on the American Idol season ten finale below: