You make a valid, if not startling, point.
IF someone did have a PD ... or frankly ... was just an unpleasant person... and found themselves unsuccessful in real life, (friends, lovers and such) ... the internet is a place where they can learn/practice masking their issues. Or masking them sufficiently to have some kind of social life.
This is not to suggest that a good number of people who socialize online have issues! It simply means that the the internet gives them a better cover and makes it much more difficult for others to get the best "read" on them.
Questions...
What part does missing... or, let's be honest
ignoring... red flags played in anyone's online dating?
Dating is often the first step we take when we're attracted to someone and want to learn and experience more of them. But... we enter a very tricky place with someone once we "officially" start dating and/or call us getting together a
date. Does the getting to know someone require a "date?" Why not get to know someone and
then say, if only to yourself... I want to date this person!