Every time someone you played plays a match, their rating is adjusted according to how they did. That gives the system more info about them and so it also gives more information about all the people they played, including you. Everyone is connected to everyone else. All of the millions of games that have been recorded are taken into account for the new ratings that are calculated every day. Josh Filler's next match is going to affect your rating a tiny little bit, even though you might be six connections away from him.
If you do start to play again, your rating will be adjusted fairly quickly because those matches from three years ago are only counted at half strength.
