First, how young? Anyone under the age of 10 probably hasn't learned programming yet, so they should stick to Logo, which was designed as a
hysical programming language" for ages 4-16.
At 16, a person can start learning programming (also called computer science these days - I come from programming in the 70s), but what with school and other things, it will probably take about 4 years.
Then - programming is programming. For at least 3 or 4 years, you can't think in a programming language yet, so you develop the program in English, then code it into a programming language. And Kotlin is simpler than Java, but Java gets you closer to the metal if you need it. (And they can be mixed in the same app.)
Or you can pick a programming language and start teaching it to a "young developer" and end up with a "developer", not a developer. Someone who gets online in a programming forum and asks "What's a loop?" Of course, we have tens of thousands of "developers" already, which is why we have some pretty terible programs (or apps, if you prefer). There's a saying in the industry - "5% of the programmers develop 95% of the programs." (The other 95% ask "how do you do this?".) It also sets the "young devloper up for early failure, and disgust at him or herself for not "getting it".
The labor pool for experienced Java programmers is at least two orders of magnitude greater than it is for Kotlin
Are you deliberately being terribly understated, or was that meant as a joke? (Poe's law prevails here.)