while certainly possible I'd argue that those successes would be extreme outliers with most falling somewhere in a more predictable reason for success, design and content plus hitting at the right time for example. Arguing the extreme outlier is almost always a good way to get discounted. Weird random patterns drive unlikely stuff in the real world, but it's definitely not the norm.
It is nowhere near as unlikely as you think.
The Model T?
Terrible vehicle. Especially for safety, dear God it was incredibly dangerous to drive. But it was
cheap, and it was (relatively)
rugged, and it was easy to make. Yet there's a reason we don't use
plate glass windshields anymore, amongst many other faults in its design.
Windows? Tons of design issues. Still by far the most widely-used OS. But being the first big thing on the market has huge value.
Mcdonald's? I don't think people like it because it's nutritious, environmentally friendly, nor good to its employees, nor even because it's amazingly flavorful. It's
cheap, and it uses lots of salt, sugar, fat, and MSG to twiddle all those basic tastebud responses.
EverQuest was the reigning king of MMOs for years, and it had some genuinely terrible design. (My dad played it for quite a long time and became
intimately familiar with how hostile it could be to the people playing it.) Yet it was called "EverCrack" in its heyday.
There are many, many, many, MANY reasons why something can be popular, can sell well, can reach a huge audience. Only a portion of those reasons are the actual quality and design of the product itself. And, before I get nasty accusations yet again,
yes, some of the design choices of 5e DO contribute to its popularity. But many, many things that have nothing to do with that also contribute: culture shifts, economic environment, changes in media, marketing/word of mouth, world events, etc., etc.
I am of the opinion that a majority, not a massive one but a majority nonetheless, are actually unrelated to what you read between the covers of the 5e PHB, DMG, and MM. (
Certainly unrelated to the design quality of the DMG, or should I say general lack thereof.) I am and have been further of the opinion that, as 5e ages, criticisms of what
is in it will grow with time. This has been borne out thus far, though I admit much more slowly than my (likely biased) expectations. But it used to be nigh-impossible to make any criticism at all of 5e. That is no longer true, even without factoring in the OGL debacle or other WotC foot-in-mouth disease, and hasn't been true for probably three-ish years now.
Hell, I was making the exact same criticisms of the 5e DMG, eight or nine years ago, that people are now making today. To the point that even avowed 5e fans will get annoyed at the suggestion that people would defend the DMG's faults, e.g. "yes yes we know the DMG isn't great
can we move on please", when literally as little as three or four years ago people were doing exactly that, declaring it good or even great and dismissing any criticism as unwarranted and incorrect....
often on popularity grounds.
Now, don't mistake me. I get that this is a prediction of future trends, and I am no fortuneteller. But if past is prologue, and if 5.5e is as minimally changed as I expect it to be, then it isn't alarmist in the least to say that five-ish years from now, there will be rather more criticism than there is today, and much of it will center on things that can't be fixed iteratively or gradually.
Which was my thesis.
I even explicitly said, repeatedly, that a balance between stability and change is needed. Too much change and you drive people away. Too much
lack of change and people slowly get fed up. Iterative change tries to have its cake and eat it too, and in fairness it actually does a decent job at that. But there are some things it
cannot fix, even in principle—and as those things remain fixed points for longer and longer stretches, they will chafe more. That is the nature of the beast.