The rivalry system is broken

I find whenever I play a big country, the game can't decide if certain countries are valid rivals or not. In my last England game, Scotland switched between being a valid rival and an invalid rival 3 times in the first 20 years of the game. The same thing happens when I play the Ottomans and EU4 can't make up it's mind if Hungary, Mamluks, and Qara Qoyunlu are valid rivals or not. I also have noticed the AI makes nonsensical decisions about who to rival. Every game Spain and Poland or Muscovy rival each other, which makes 0 sense.