The quote is the wrong way of looking at this. The typical rate of successful primary challenges is only 3%. If you take that to 10% its an enormous success, incumbents will say "if I oppose crypto then I triple my odds of losing in a primary, better not do that."

It's not quite like that, though. 90% of their funding supported candidates that lost or opposed candidates that won -- they opposed the winning outcome. They supported the winning outcome with the remaining 10% of their funds, but here they pushed on the side of the contest which was already a lock anyway. So it isn't clear that any of the money they spent achieved anything.