Giving detail that you probably already know in case it's useful for others.
When you have "showdead" enabled in the settings you can see all the "dead" posts.
A dead post is one that has been marked such that it only appears if you have the above setting enabled and prohibits replies to it. This is usually because it's deemed too off topic or otherwise obnoxious to have value.
The post in question was probably marked dead and because it wasn't particularly offtopic or obnoxious then a shadowban is a reasonable assumption. This could be further verified by noticing that that person's comments are almost all dead. This suggests either they're shadowbanned or are remarkably consistent at producing offtopic/obnoxious posts without getting shadowbanned.
When you have "showdead" enabled in the settings you can see all the "dead" posts.
A dead post is one that has been marked such that it only appears if you have the above setting enabled and prohibits replies to it. This is usually because it's deemed too off topic or otherwise obnoxious to have value.
The post in question was probably marked dead and because it wasn't particularly offtopic or obnoxious then a shadowban is a reasonable assumption. This could be further verified by noticing that that person's comments are almost all dead. This suggests either they're shadowbanned or are remarkably consistent at producing offtopic/obnoxious posts without getting shadowbanned.