I disagree with you on this one. For me, the game was like a puzzle - trying to figure out how to breed 2 cats together to produce a fancy cat (in my case, a dracula since that was what was hot when it started). The excitement when I was able to figure out the traits need and actually produce 3 Dracula cats was there. And, the end result of my win was selling them for a nice little profit.
This was definitely fun for me when I played it, but has since lost its muster because the over-population of cats with no population reductions has caused an over saturated market. Even though I don't really see as a long-term play, it will be remembered as the first crypto game to take off.
Now, there are other ones they call "games" which, like you said, don't have any gameplay. You are collecting something to try to sell for a profit. But, cryptokitties definitely had some logic puzzle aspects to it.