Hmm, but what if the compiler doesn't use the optimized constructs, e.g. floating point optimizations targeting numerical algorithms?
That said, even if the exact heuristic Wirth used is no longer tenable, there's still a lot of wisdom in the pragmatic way of thinking that inspired it.
You could try to game the system by combining such a change that slows down compilation with one that compensates for it, though, but I think code reviewers of the time wouldn’t accept that.