I disagree. The number of factors that go into producing wort (and hence into beer) are plentiful, and there's been plenty of science done over the years as to how different parameters affect the result. Different systems may (do) affect those parameters differently, and hence will produce different beers. As an example, does a step mash produce a different beer than a single infusion? Yes, of course. Does a well-tuned PID deliver tighter control of step mash temperature than a thermostat control? Yes, absolutely. Is a tightly controlled step mash going to deliver a "better" beer? In some cases yes, in some cases no, but there's not likely to be a negative outcome if done properly. But the tightly controlled PID recirculating system can adhere to designed recipes much more effectively than a single-infusion, multi-infusion, decoction or thermostat-controlled recirculating system, and loses nothing in comparison (maybe decoction in some aspects, but that's a different kettle of wort).
Now, how many of us hobby homebrewers repeat the same recipe often enough, or have finely-tuned enough palettes, or dial in and measure against our recipe design well enough to tell the difference? Probably not many of us, but that doesn't mean a difference isn't there. Is the Braumeister specifically going to produce "better" beer than a BZ or Guten, all other things being equal? I suspect not, or only very slightly, because I think it's strengths are fairly well balanced by those of the BZ/G, but that doesn't mean that the premise is flawed and worthy of scorn or being labelled "crap".
Just because one person can produce a better beer from a kit and kilo than another person can with a top of the line (according to your metric of choice) system doesn't mean there's no difference in the system, because the hardware's not the only factor. Brewer skill, ingredients and technique are probably more influential than hardware, but they all affect the final result.
I'm not even going to touch the straw man Bentley vs Datsun.