This is not a compelling argument. I'm not going to stop using a powersaw to cut beams just because another contractor refuses to use anything but his handsaw.
Besides, reading implicit types has _never_ been an issue on any team or collaboration effort in the 30 years of my programming experience and I find it _really_ hard to believe anyone that claims it is a bonified problem for readability. In fact the complete opposite is true for me, personally, that too much information in front of me becomes noise and the signal gets lost.
They're not talking about someone using a hand-saw, they're talking about someone using a powersaw from a different manufacturer. Or, y'know, a table saw, or a CNC machine. Kotlin has tight integration with one particular IDE, not with all IDEs; let alone with things that are powerful in ways orthogonal to the ways IDEs are powerful, e.g. Emacs.
Besides, reading implicit types has _never_ been an issue on any team or collaboration effort in the 30 years of my programming experience and I find it _really_ hard to believe anyone that claims it is a bonified problem for readability. In fact the complete opposite is true for me, personally, that too much information in front of me becomes noise and the signal gets lost.