Earlier quoted context omitted.
I sincerey hope nobody reads this and thinks "I should start ghosting too". We want less ghosting in this process, not more.
Operating with integrity in a domain where nobody else is is a shortcut to getting fucked.
Yes, ghost those who don't take “sorry, but no” (or more succinctly just “no”) for an answer, especially those who have done so repeatedly (those are a time sink and deserve ghosting), but I wouldn't take it as my default position. Try not to become what you hate.
OK, so I tell a bit of a lie: ignorance is my default and only response wrt LinkedIn these days. I see the “you have messages/requests / people are looking at you” alerts regularly by mail, but I've not logged into the site in half a decade or more which anyone looking at my profile (rather than just being a gattling-gun invite spammer or similar) could probably tell with ease (the fact they bother contacting me is a good indication that they aren't a useful lead!).