It should be emphasized that playarounds are held to at least the same standards as "conventional" TASes. I'd argue they're held to even higher standards.
Few playarounds have been published and there are some consistent themes among them. The majority of them (26 out of 41 movies) are fighting games, probably because that genre lends itself to playarounds over strict "fastest completion" TASes. Six additional movies are in the sports genre, probably for the same reason. There are also games that are part of iconic series: Zelda, Mario, and Tetris. Those movies were probably published because of their respective series' popularity and the fact that they tend showcase glitches deep within the game. Those glitches were, in turn, discovered because of their game's popularity and the fact that their code has been picked apart.
That leaves just a few games that are (at least partly) outside of those major categories: Brain Age, Scribblenauts, Gradius, Oddworld, and Family Feud. Like the other games, these games tend to showcase major glitches and/or unexpected gameplay.
In short, it is quite possible to get a playaround published, but because of the inherent speed/entertainment tradeoff in that goal choice, the entertainment value has to be through the roof.