Yeah, if you treat it as javascript vs python they're likely correct (I'm not that familiar with js). The article and original comment were about function vs imperative though, so I assumed half decent runtimes for both.
True, but now you're relying on a specific implementation and optimization of the compiler, unless the language semantics explicitly say that lambdas will be inlined.
This is true of literally anything and everything your compiler emits. In practice the functional style is much easier to optimize to a far greater degree than the imperative style.
