The change I proposed is not disruptive in any way.

As for the billion dollar mistake, a null pointer reference results in a seg fault. But the array decay results in buffer overflows, the #1 problem in shipped C code, and the buffer overflows result in memory corruption. Memory corruption is much, much, much worse than a seg fault. For example, buffer overflows are exploitable by malware. Seg faults are not.

Hence, the array decay is the worst mistake.