I'm not so sure. There are only a handful of popular ad-blockers, and on most people's browsers, they update automatically. If PageFair's techniques can be defeated, they'll be defeated systematically and simultaneously for every ad-blocking user as soon as the workaround is implemented. So it's basically binary. If PageFair just doesn't work at all (or can't be expected to for a meaningful amount of time), then it's not going to sell well.
Contrast that to McAfee. They're fighting a long, generally losing arms race with virus writers, but note that in practice they still protect your computer from a lot of viruses. So users need them. If all the viruses in the wild could all be simultaneously upgraded to circumvent the scanner, it would be a different story and everyone would just think of virus scanners as a thing that doesn't work.
Contrast that to McAfee. They're fighting a long, generally losing arms race with virus writers, but note that in practice they still protect your computer from a lot of viruses. So users need them. If all the viruses in the wild could all be simultaneously upgraded to circumvent the scanner, it would be a different story and everyone would just think of virus scanners as a thing that doesn't work.