The consistency of PDF rendering has nothing to do with it being an ISO standard. It's based on a completely different model that made different tradeoffs with respect to user-end flexibility. It was also controlled by a single company for 15 years.

TimBL and the W3C were pushing for new payment models 15 years ago (and probably earlier). This is why HTTP has 402 Payment Required. There was a W3C micropayments working group back in 1998: http://www.w3.org/ECommerce/Micropayments/ .

This stuff would be hard to get right in a vacuum. It's even harder when you're trying to get groups with competing interests to agree on something, especially when you have as little leverage as standards organizations tend to have. The view put forward in the last half of this essay is naive.