The language itself is not more complex to onboard. For Scala also not. It feels great to have all these language features to ones proposal. The added complexity is in the way how expert code is written. The experts are empowered and productive, but heightens the barrier of entry for newcomers by their practices. Note that they also might expertly write more accessible code to avoid the issue, and then I agree with (though I can't compare to Python, never used it).