Says who? There are dozens of NES bootleg games you will find here that are definitely run on NTSC (pretty sure most if not all famiclone games run at 60fps anyway). I played this on an NES via Everdrive.
I don't quite understand the fascination people have with Dendy mode. When these games get released into the US and European markets they use exactly the same ROM, see Silent Assault. The famicom shaped cartrigdes work on official famicoms, which is how I run this game.
Super Game made games intended to be played on Dendy region consoles. Although it is hard to tell with this game as it does not use the original game's music, opting for original tracks instead, their other ports which do use the original music, are at a wrong, faster tempo, but the right pitch on NTSC. On PAL, they are at the right tempo, but wrong pitch. On Dendy, the tempo and pitch is just right.
In other words, just because a game plays on NTSC or PAL doesn't mean it's playing properly.
What @crazyjesse said is that these unlicensed game carts can still be played on actual famicom hardware since they are basically famicom carts, and some have been released for the NES in physical carts. You say intended, fact is companies like Joy Van for example had their games published for the NES as well, the only difference could be a title screen name change, but the point is they used the exact rom so it's fair to say all unlicensed famiclone games can be played on NTSC, regardless if you think they aren't playing "properly". Not that it matters that there's already a couple Super Game leaderboards here some with more than 1 runner, all play on NTSC.
In other words, if it exists on FC or NES, we'll play it there.