I've run into problems repeatedly when it came to DP cables. The issue is always the same: lack of enforcement and no barrier to entry allows for too many entrants, whose motives are up to consumers to discern, wasting time and money in the process. What I originally saw as a benefit of an open standard, as it turned out, was in fact a benefit (for consumers like myself) of the closed/high priced standard—which ended up costing me less, in the process.
Something the original article doesn't mention regarding multi-stream (MST) is that it could be used in situations where a defined standard for a certain resolution/refresh rate didn't even exist, to still make it available. For example, the earliest 4K/60Hz monitors relied on DP 1.4's (or 1.2's? I don't remember) ability to address multiple displays, to send two signals—each to cover one half of the total screen area, i.e. 1920x2160/60Hz, for a combined total of 3840x2160/60Hz—to the same display, which that display then used to internally drive two virtual screens, added seamlessly to create 3840x2160/60Hz. At the time (around 2013 and for a while thereafter), the maximum supported in single stream configuration (or by the existing HDMI standard at the time)_was 3840x2160/30Hz.
You'd think this would be a point in favor of DP—which is certainly what I assumed, at the time. Unfortunately it soon became obvious that because there was no enforcement of DP compatibility—of claiming to support up to a certain version of DP fully, in other words—this meant that most cable manufacturers felt no compunction about lying shamelessly, claiming to support e.g. the 1.2 or 1.4 version at the time (which implied supporting its MST and bandwidth capabilities fully), while doing nothing of the sort.
The lies did not stop there, by the way. If I could, I would here post a photo that I would happily take this very moment of such a DP cable—which didn't come especially cheap at the time, btw., in fact it took three days' worth of effort, a lot of handwringing and plain luck in the end (not to mention wasting money on several dud cables, each claimed to be fully compliant, on top of the additional money required) to finally purchase a cable that actually was compliant—which claimed gold plating as one of its features. Some fine gold that was, with black spots on both sides of the yellowish anodized plug, where the metal had oxidized! Why? Because, as I came to realize, the high barrier to entry created by the high licensing fee of the HDMI group also acts to keep away a bunch of unscrupulous manufacturers, which is purely a benefit to consumers!
In addition, I've never had problems with regular size HDMI plugs—in particular, with removing them. I can't say the same when it comes to DP (especially full sized), which frequently (by design?) have a button that needs to be pushed in to release a lock that holds the plug in place. The problem is, too many times it's very difficult, if not impossible, to push down this button. Worse yet is the ambiguity that this creates: is the button fullly depressed? Is it stuck? Am I getting ready to rip out, or at least damage the underlying hardware, or even just the cable itself? These are thoughts I've had nearly every time while trying to unplug a DP cable, while HDMI (at least the standard size) slides out smoothly, as nothing is put in place to hinder this. In addition, this works well time after time, meaning there is no mechanical fatigue like with mini- and mico-USB.
I can appreciate the idea that DP, when used internally (e.g. in laptops, where any shortcoming would directly reflect on the manufacturer of that laptop), or embedded within another standard, is a great idea, where its low barrier to entry /can be/ (as long as the savings are passed on, that is) a benefit to consumers. However, to claim the same in all applications is simply not supported by the real life outcome of either implementation philosophy.