Why is playback speed limited to 4x?

I'm really just looking for an explanation for why the maximum playback speed is limited to 4x. I understand that a higher speed (if it was possible) would be increasingly more taxing on the cpu to render if resampling was chosen, but it seems to me it would not cause any issues besides that.

Right now I'm re-rendering a bunch to achieve a speedup of 256x or so, which works but it's annoying and it seems like I'm jumping through hoops to circumvent an arbitrary and unnecessary limit put in the software for an unknown-to-me reason.

Thanks to anyone who can answer.