This symbol is not ominous; the glider doesn't die. It moves through four states, arriving at this steady state:
XX
X X
X
I'm surprised that the author wrote such a lengthy article without making sure that the premise is true. I think he misread the engraving and transposed the stray dot to the left, like so:
"Technically the glider becomes a known static shape. But for this active and useful little craft with its wiggly diagonal propagation and useful character, it is as good as death." Though it is fairly easy to miss, it is stated in the article. The author is using "death" to mean that the shapes stop changing, not that the dots disappear- which is not the same meaning you and I thought of at first.
