Are they right?
Springfield Armory's XD 9 is an example of "new technology" handguns with its lightweight polymer frame, rust resistant finish on steel parts and manner of barrel lockup. Glock pistols are now several years "old," but continue to sell very well. Like the Glock, they command a large section of the American police market today. They are extremely reliable pistols and simple to use. The SIG-Sauer P-Series handguns are newer designs than the single-action autos and some can be had in double-action-only. In that regard, they do match the single-action in having but one trigger-pull to master. The DA/SA auto has been around for decades now, but is still newer than the single-action. Is it really superior?
In some ways, I do believe that some of the newer designs are better, but by how much can be more theoretical than real. One area might be reliability.
Most of the time, the newer pistols can be counted upon to feed about any available JHP ammunition on the market right out of the box. In the past, pistols like the Browning Hi Power was not unknown to choke on certain types of hollow points. Current Hi Powers no longer use the old classic humped feed ramp and in many examples I've shot long term, they feed and function fine with about any ammunition one cares to use. Likewise, the 1911's of year's past would frequently fail to feed much besides "ball" ammunition. These days, they come "throated" and most will feed most JHP ammunition, particularly if it has a rounded ogive. We do see complaints concerning some guns not reliably feeding some rounds and about as many about the slide not locking open on the last shot or locking open too soon. There are many reasons for this and most can be fixed pretty easily. I think one reason for these problems with the 1911 pistols in particular is that a myriad of makers produce them and there are many, many companies being used to make small parts. In this there will be dimensional variations and the 1911 design doesn't seem to tolerate that too well. However, with those that work reliably, they can be extremely effective pistols as they have been from nearly the time of the US Indian Wars to the days of the personal computer!
In a time when fewer folks shoot and where administrators are concerned with lawsuits anytime a service handgun is fired, the newer designs have found a home. This is understandable. One's perception of what is "safe" or "dangerous" is that person's reality, at least for that moment. If they opt never to investigate or delve a bit deeper, they can easily make wrong assumptions as to fact. Some opine that the cocked and locked automatic looks "too aggressive." One cannot argue with emotion though those familiar with "Condition One" frequently tend to favor it for fast and accurate shooting.
The 1911 pattern pistol remains a favorite to this day. Designed in a very different era, it can still deliver when called upon, be that in a hard-fought match or dark, danger alley.
It's been my experience that the single-action automatic carried cocked-and-locked is not unsafe. It is less tolerant of unsafe gun handling than a pistol with a longer, heavier double-action, but with proper handling, the mechanically sound single-action automatic will not fire until intended. (It's interesting to note that there's a rather large contingent of shooters who consider the Glock unsafe and cite numerous negligent discharges to back up this view. I think the Glock is "safe," but like the single-action it is not forgiving of unsafe handling.)
With regard to manufacturing methods, the older, single-action designs might be considered obsolete or at least not as "cost effective" compared to the newer guns.
I've proven to myself at least that the easiest pistol with which to get quick and accurate hits remains the single-action automatic. I've noticed on many occasions in tactical training that when some pretty fast shooting, particularly involving distance was required, the officers using DA/SA automatics preferred to start with their pistol cocked, if possible. The single-action auto is designed to start off cocked and allows the use of a safety up until it is being brought to bear on the target. The Glock does offer a fairly short trigger-pull compared to other newer pistols, but even it does not have the short reset of the 1911. I have never been able to shoot any semiautomatic at distances of 50 yards and farther better than an accurate single-action.
While some really don't like the double-action first shot and single-action transition thereafter, I've not found it to be as "bad" as some. However, it is not as "easy" as with the single-action.
It is interesting to note that here in the earliest years of the 21st century, some of the "high speed - low drag" police and military units having a choice go with the "ancient" 1911, albeit with features not available on the original guns and this is sometimes an overlooked point. You see, the single-actions have not just been frozen in time. Their actions and manuals of arms may have remained the same, but features have been added and refined to make them very capable of dealing with about anything a handgun might be called upon to "handle." Colt, Kimber, Springfield Armory, STI, and others continue to refine the 1911 single-action as it approaches 100 years of age.
Not as popular in the US as the 1911, the Browning Hi Power is now available in several configurations having extended, ambidextrous thumb safeties and easy to see high-visibility fixed sights. These pistols shoot very well and are extremely reliable. I'd prefer to use one of these or a 1911 in a fight if required to use but a semiauto handgun.
Please don't get me wrong. I have nothing against many of the newer designs, but I emphatically do not believe that the single-action auto is obsolete; not if getting bullets where you want them in a short period of time is the goal. Training with them is essential, but in skilled hands, the single-action automatic can do miraculous things.
If you prefer the DA/SA, Glock, P-7, or other handgun type to the single-action, I have no problem with it at all. People sometimes simply prefer other than single-actions and some are given no choice by mandates from bosses to agencies, but I do think that simply bypassing the single-action because it's "obsolete" is a mistake.