If output of man invoked without any arguments causes a critical bug right before the launch day, or the equivalent of your windows opening randomly in the middle of the night, you have much bigger things to worry about than that easter egg. (I doubt a true Graybeard would ever find oneself in such a circumstance.)
If bit flips become more common as transistors get smaller, that’s certainly going to throw a much less controlled wrench in the works.
It might not be critical bug. But it certainly could be failed build job. Which you then have to rerun wasting time or manually hunt down and waste time tracking where it comes from.
And something like this printing out in error could indicate that you have been compromised and you should lock down everything. Verify that you full system is clean and go through all of the logs.
This ad-hoc approach looks very suboptimal as a threat detection heuristic. Judging about your system’s security by whether there are binaries that behave in upredictable ways means a game of whack-a-mole against buggy programs (which is 100% of them, remember?), while letting real threats go by.
A way of making sure your binaries are trusted is supply chain security, which starts with not obtaining them through unvetted sources. If in that situation a known-trusted man says a funny joke at midnight, your spidey senses would not be triggered.
In other words, if there is a way for suspect binaries to get into your system, you have a bigger problem. If there is no such way, you can be sure it’s benign behaviour, a bug in the program, an Easter egg, or even a bit flip or some unlikely interaction of factors. If you are not sure whether you have eliminated all such ways, sure, it might seem like a cause for worry—however, I don’t think attackers you should really worry about would try to make themselves noticed through jokes with Western cultural references (or through any jokes for that matter, or in any way at all).
What makes you think they didn't read the submission?
Occurring with -w was a bug that happened to be located in the easter egg code. It wasn't the actual easter egg. If you hit it as intended, you do have bigger things to worry about.
So you could argue that it's bad to have extra lines of code because that's 0.01% more space for bugs to hide in, but 0.01% extra code is hardly something to launch objections over. Nothing about that is easter egg specific.
If bit flips become more common as transistors get smaller, that’s certainly going to throw a much less controlled wrench in the works.