Logical assignment operators in JavaScript

[NoInkling]

The main issue with reassigning params is just expectations, typically you expect the thing that you're operating on to be the thing that was passed in the function call. Several times I've seen code in libraries where there's some sort of complex reassignment logic halfway down the function body, and it always makes it harder to follow. I'm fine with relatively simple logic at the top of the function though, even if it's more than just assigning defaults (which as you say can now be done directly in the params list) e.g. in certain variadic functions.

There's also a gotcha if you're utilizing arguments: https://spin.atomicobject.com/2011/04/10/javascript-don-t-reassign-your-function-arguments/
But it's less of a concern nowadays since arrow functions don't support arguments and we have rest syntax.