why do all their games run at like two frames per second

They pushed NES way beyond its limits. Realistically, NES could only handle few sprites on screen. It already struggled with bmups, now imagine adding more interactive objects to the scene.
RCR was playable, but that feudal Japan game they made was a total mess. Looks gorgeous though

just play the pc engine versions of the kunio games
river city ransom, super field day, and super dodgeball are all definitive ports. double dragon 2 is also a remake of the nes version and its fantastic
the kunio soccer game is ok on pc engine (better than nes) but has a better version on genesis

>>11813780
>They pushed NES way beyond its limits.
No, TMNT games are way more impressive. And their nes shit isn't even that bad compared to the DD arcades' framerate.