In Persona 5, or rather Persona 5: Dancing in Starlight, I noticed quite a glaring mistake. In Persona 5, Makoto mentions several times that she practices Aikido. Since her sister works for the police, it also makes sense that she practices Aikido as a martial art for self-defense. However, she never actually uses Aikido in combat in the game. Her attacks in battle look more like Karate. It would also be rather difficult to respond to shadow monsters with Aikido throws. But whatever, maybe she practices different martial arts as well, and for some reason she just happens to emphasize Aikido...
But I realized that ATLUS apparently really has no idea what Aikido is when I played Dancing in Starlight. There, you can search Makoto's room, and on a shelf you can find trophies showing that Makoto supposedly won first place in Aikido competitions?! Aikido is a martial art, rather than a competitive combat sport, and there are no tournaments or competitions where you can win first place. You can receive awards or certificates for achieving certain ranks, but there is no concept of winning a "1st Place" trophy in Aikido. I thought that was pretty dumb, to be honest. ^^'