I think it’s a typo and they meant unused parameters.
_ = myvar; // TODO remove
easily for all function arguments when prototyping.
I agree it can be cumbersome, but I am not sure it is a bad thing.
Should have been a warning. Baked in from day-one, easily makes that a CI check without hampering development.
When these languages tout fast iteration cycles, yet for a single-line code you have to do a recursive, n-step compilation of everything that might also get unused is literally insane and indefensible position.