I think the author intended it as a valid criticism, though it's hard to tell given the passé stylistic choice that calls back to early internet (I am nostalgic for those days sometimes). However I disagree with that as it's just one more, fairly silly, obstacle to overcome. If this "replacement" ever did, theoretically, been seen as suitable, all that would happen would be that attack code would suddenly see an increase in quality.

If you've done any research into quality malware, exploits and the like (both domestic and foreign), the quality and often elegant solutions they come up with will not be somehow kneecapped by an emoji. It also only needs to support inputting one emoji in the event that someone uses this out in the field; not hard to do in shellcode.