I think supply is an issue, but I also think the author added to the problem by releasing a game that doesn’t have appealing graphics, gameplay or sound. Where as many much of the unity “shovelware” is exactly the opposite.
I think the difference of interpretation we're having is that I think you are interpreting "Unity shovelware" to mean "If it's Unity it's crap", which nobody who follows that space could easily defend (a lot of high quality well known games and publishers use Unity). But a lot of shovelware uses Unity, because it's easy to get assets for and publish with.
It's sort of like saying "Java enterprise crap-ware". I wouldn't assume that means all Java programs are crap, or that all enterprise software is crap, but that of the crappy software targeted towards the enterprise, a lot uses Java. That's not an indictment of Java, and might actually be the opposite, given that it has qualities that cover up other poor choices.
I think you mean the opposite: the bar is super high because the chances of watching something new are low ... it's more difficult.
Now that game engines are commonplace, free and work better than what any single developer would be able to come up with after a lifetime of hard work the end result is that games have a very hard time to differentiate themselves from each other. There isn't really an unlimited space of game scenarios out there, even in the days of the 2D arcade games after a couple of years it became much harder to come up with something truly unique.
It was never difficult to "come up with something truly unique".
Your unique thing might be rubbish, but that's not the problem for the millions of shovelware Unity asset flips.
Jim Sterling has covered this at length, even running a competition to show that people can take a horribly over-used cheap asset and do great original stuff - if they try. Asset flips don't even try.
The are tens of thousands of games in which you are an elite soldier running around shooting zombies. There are zero games where you're a pot plant using psychic powers to create sculptures.
Like Hollywood the video game industry chases trends until they're beaten completely to death, and then goes one more round just to make really sure.
Did we read the same article?
Not only the total number of games, but the rate of their release seems to be geometrically increasing! Holy crap. And while many of them are Unity shovelware, etc., many are polished games that a lot of effort went into. A tiny percentage are hits, but most are forgotten in the deluge.
To me that reads as someone that's fully aware that some people are putting a lot of effort in and making good games (Unity or not), but is upset by the realization that quality doesn't seem to be nearly enough. The problem is not (just) that a lot of crap is being released, but that a lot of everything is being released, good and bad. So much so that even the good things can't make good money because supply has so far outstripped demand.
It's sort of like the Netflix queue problem. I'm continuously adding things to my Netflix queue that look interesting, but my time to actually watch them is such that my chance of getting through even a majority of the queue is almost nil.