>>280547154
There are a few things I can think of.
1. He's just saying what a typical fan girl would want to hear from him.
2. He's suspicious of Uta being Cure Idol and wants to get to the bottom of who she is for one reason or the other.
3. Toddler Uta really was the person who inspired him but he doesn't feel bothered to reveal it since she herself doesn't remember.
Toddler Uta having already met Kaito or Purirun before the season started is such a crack theory, but the season's weird enough that I can't completely dismiss it.