I heard a quote somewhere that went along the lines of "the modern era has passed Williams by" and it's true. "The car is King" is no longer enough. McLaren and Red Bull ensure that performance is "optimised" or "off the hook" (depending on team) at every conceiveable point.
Williams have a cutlure derived from having a car 1sec/lap quicker than everyone elses. When the car is that good, it doesn't matter what the factory does, what the mechanics eat, what the marketing dept do or don't do...
Even if we were building the quickest car F1 just isn't like that any more. The margins are so small the slightest advantage needs to be found anyhwere.
Of course, building a car with a working underbody is the first opportunity. But not far after that, they have to get serious.
If MJP can help that then fair enough!