Look at it this way: Bosch decided it was better to spend a small fortune of R&D to try to avoid the patent than to pay the license fees. And even now they haven't settled the resulting lawsuit - they'd rather fight it, because the likely outcome of the fee is not "paying up" but "scrapping the entire product line as a net loss".
Also bear in mind that this technology is a major portion of the total price of a saw - up around 50% on cheaper saws. So it's going to massively increase prices, and also increase SawStop's margins. They didn't just ask for 8%, they asked for 8% while lobbying the government to increase the price they're taking margin on and ban smaller competitors.
This looks like the other form of patent abuse - where instead of trolling you make a product people can't avoid and crush competitors with patent suits.
It also seems strange for that to be a percent instead of a fixed cost since the feature is the same for all models of a saw.