First, the action has nothing to do with the problems inherent in the trigger group. If you put the same trigger group (and matching bolt) on a Winchester 70 (pre or post ‘64), Mauser 96/98, Savage or custom action, you’d have the exact same problems. Likewise, if you put a Timney, Jewell or Anschuetz trigger group into a Remington, you wouldn’t have the issues that Remington has with their triggers.
Second, the reason why the majority of custom action makers are cloning the Rem700 is for the same reason that the Rem700 is was designed in the first place: the round receiver is easier to dial in on a lathe (or now, on a VMC). The flat-bottomed receivers (eg, Win70 and Mauser 98) take more time (and therefore higher labor costs) to either manufacture or to blueprint. Remington isn’t going tighten tolerances because they won’t gain much from the exercise. They’d get more improvement from adding a premium barrel on their existing actions than they’d get by making something equivalent to a Stolle, Defiance, BAT or Border action.
As for money spent on custom guns: Big money isn’t spent on Remington-based rifles. People spend nice money, but not big money on Remington customs or clones. Big money is spent on pre-64 Winchester based rifles or Mauser (or Mauser clone) action based rifles built by custom smiths. I’m talking $8K and up for a rifle, some into the teens with engraving and fancy checkering jobs on really nice wood. Want to see a Real Big (NB capital “R,” capital “B”) money rifle? Look at some of the arms produced by Hartmann und Weiss in Germany. A new rifle of theirs based on a Mauser or side-lock action could set you back $50K. That’s what I consider a “high quality rifle.” A custom bench gun based on a Remington clone might be very accurate and quite nifty in benchrest shooting, but it won’t be suitable for hunting, nor is it especially collectable. To each their own - I’m not saying the Remington-clone market is a bunch of bad rifles, only that they have a narrow application. Oh, and they’re (comparatively) easy to build. As a result, the very high priced bespoke rifles aren’t built on Remington actions.
There is still and always has been a problem in the Walker trigger group. Whether someone (or a group of people) have never seen the problem evidence itself is not proof that the problem doesn’t exist. Look at the patent drawings and think through how the trigger group works. Now put a big of schmutz behind the connector, put on the safety to lift the sear off the connector and let the connector wedge forward. Now release the safety. There’s a reason why Remington now tells you to ‘never pull the trigger while the safety is engaged.’ It is because they know that the connector can work out from under the sear and *not return* when the trigger is released while the safety is on. This problem doesn’t happen with a Win70 trigger group, nor a Mauser group, nor a Timney, Jewell or Anschuetz trigger. It *can* happen on those triggers if someone gets into the trigger group with a file or stone and really makes a hash of things, but as they come from the factory, those trigger groups don’t have a situation where only dirt can make the trigger group malfunction in the way the Remington 700 “Walker Fire Control System” can. None of them have the connector (which was another Remington expediency to make it cheaper to manufacture). The Walker trigger group can, from the factory with no adjustment or malpractice by a gunsmith, can accumulate enough dirt behind the connector to malfunction. Start making the trigger too light and it just happens more easily.
As for the receiver, Remingtons (IMO) are generally more accurate and / or easier to make accurate than the model 70 or a Mauser. I'm a Savage guy (lefty), and they are probably a bit more accurate out of the box than Remingtons, BUT they are not a particularly pretty rifle to my eye.
To each their own, but I think the CNBC documentary was more a hit piece than a shining piece of journalism.