"Random" is used by most people to mean "random with an even distribution".

A weighted die is still random, but with an uneven distribution. This is effectively a 2^16-sided, weighted die.

My argument to follow your analogy is.

It's not a 2^16-sided weighted die. But a 2^16 - 1 sided fair die.

I am not saying there is no bug. I am saying the bug has no practical impact.

Sure if you are that one guy that is getting these values raw from the instruction and comparing to zero for some purpose then you are in trouble. But I am pretty sure no one is doing that, especially given that the bug surfaced after 6 years of millions of users.