The undertone of my post was that it's either him or Usman (I'm gonna edit my post afterwards), so that was in no way a jab on Kamaru.
I agree with you that when you look at performances you can make an argument that Usman has been more dominant. The Jan loss however doesn't really count in this discussion because that happened in a different weight class.
I would say Israel has separated himself more from the pack. If I have to bet, I think Usman will lose his belt before Izzy does. Colby is still a credible threat despite the first loss, Wonderboy and Luque can pose some stylistical challenges, etc. At MW the only guy is Whitaker who Israel has already beaten in a super dominant fashion.
Again both are super dominant champs and really it depends on what you choose to focus on.