[vbezhenar]

> What would be the purpose of such a simpler vector format?

To allow simpler implementation for both consumer and creator software. To achieve better performance (lower size, faster parsing and drawing).

> The only use case I can think of is for standalone vector graphics images, but PDF or SVG is often good enough for that.

SVG has some problems as a graphics format, which are highlighted in this thread. I'm not sure about PDF, I never saw it used as a vector image format, so can't judge much about it.

[userbinator]

PDF's graphics are an optionally-compressed-binarily subset of PostScript, which manages to be both human-readable and relatively simple to parse.