Bill Ruger didn't get to rewrite history just because his fan boys believed him. Losing money on every sale is the easiest problem to solve. If cost was the impetus for discontinuing the Six series, all he had to do was raise the price. The fact was there wasn't enough demand for them even at the unraised price. That is what is obvious but unadmitted by Ruger. The demand for Six series revolvers was soft because they sold almost exclusively into the law enforcement and security guard market and by the time of its discontinuance, new sales in that market was almost totally dominated by the Smith & Wesson 586 and 686 -- which happened to be designed by Dick Baker, who was also the one who designed the Six Series when he earlier worked for Ruger.
Not many agencies were buying Colt Pythons, and while many were keeping their Model 19's, the 19 had become considered obsolete for those agencies which determined to use 357 Magnum. The Newhall Incident precipitated a pivotal dilemma where agencies were unlikely to continue to mix their use of 38 Special and 357 Magnum the way Bill Jordan had long advocated. The agencies that were buying a lot of new revolvers were the ones going with 357. Just like the Model 19 was perceived as inadequate for exclusive use of 357, so was the Six series.
One of the major flaws of the Six series was the yoke-mounted gas ring. Bill Ruger was personally aware of this and was known to specify special production of cylinder-mounted gas rings to fill law-enforcement contracts. Of course Dick Baker was aware of it too, and marveled that S&W had changed the 19 from a cylinder-mounted gas ring to a yoke-mounted ring. He realized this was a step backward. One of the first engineering changes he made when he arrived at S&W is to put the gas ring back on the cylinder, redesigning it to address an issue where it would sometimes come loose. This was introduced with the 19-4 and 66-1.
The change S&W had made to move the gas ring to the yoke (which was not accompanied by a dash number) resulted in a greater undercut of the barrel extension (the forcing cone). It was this, combined with the spreading practice of shooting high volumes of 357 or Winchester's 38 +P+, and the trend to shoot lightweight bullets (110 grain or 125 grain Supervel) that caused these revolvers to become considered weak. Nobody would argue that the 19 was perceived this way, and that plenty of gunwriter ink was spilled on cracked forcing cones due to the damned cliche of "a steady diet of 357 Magnum." In fact, the problem with the 19 was nowhere near as widespread as the gunwriters made it out to be (beca, but if it was present with the 19, it was just as much so with the Six series.
Ruger fan boys will point out that the Six series didn't have the flat on the barrel extension that K frames did, but it was not this flat alone that caused K-frame failures. The K-frame rose to immense popularity, far greater than the Six series ever saw, in the 50's and 60's when this problem was never heard of. It was not the flat alone, but the thin barrel extension that the Rugers also had, combined with the new fad for light bullets and high pressures that created a demand for stronger revolvers.
As a factor driving market demand, the perception of the issue was just as prevalent for the Six series as it was for the K frame. This is why Ruger hyped the perceived beefiness of their GP-100. It was Smith & Wesson that countered with a marketing position that could have been neutralized had Ruger not had to discontinue it's Six series. Smith would not have been able to poke fun at the Six's tubbiness.