You can argue the tooling is still immature... but kmp really has been taking off since cmp has gone stable on ios. The kmp library ecosystem is even getting quite large. Also, kmp has very distinct advantages over React Native and Flutter, they didn't just copy-paste from RN or Flutter.
Jvm desktop is honestly the target with the best support. I always build on desktop during mobile dev first because I don't need to deal with connecting a phone or emulator. Second resizable windows by default is so helpful when building for many screen sizes. Also it has hot-reload now