I’m not sure you are following my logic. For them to take every person who shares a plex server with people to court would cost an exorbitant amount of money. First they have to find them all, which is non-trivial. We are talking hundreds of thousands here. Then they have to get proof according to local laws. That already requires them to employ experts in each jurisdiction. Then they can send the letters, which have to be tailored based on the jurisdiction, which probably isn’t much, but they have to be sure it is legal to even send it. Some places (though few) it will open them to being sued if not worded correctly. Then to take it to court they will need licensed lawyers in every jurisdiction. The cost would be crazy. And for the cases they win, they won’t get much money because they aren’t sueing companies, they are sueing people.
It’s not that a person would necessarily win in court, they may or may not. But the scale of the expense is soo much higher than the revenue as to make it a very bad financial undertaking.