The original WSJ article can be opened up, but you have to be a paid subscriber to do it.
While I don't disagree with much that they say, I also do not think there is necessarily a cause and effect relationship between the factors they are talking about and the flattening of record sales.
What I think they are missing is that a big chunk of the rise in record sales can be traced back to young people who jumped onto the record bandwagon more because it was a fad than because they though records provided a better source of music. I an basing this on observations of and conversations with high school and college friends of my children's as well a conversations with many young people that I interact with through Boys Scouts and the Golf and Ice Hockey programs that I coach in.
My kids grew up in a house where music and good sound were always present, and as such my younger one has his own VPI TT and Audio Research electronics, but almost all of his friends that do listen to records do so on a suitcase record player (I can even call it a TT) that has an amp and small speakers built right in and sells for about $75 or less.
So if somebody is listening through a 3 1/2 inch full range driver, I think i is a pretty safe bet to assume that SQ is not one of their top priorities. Therefor I don't think many of them would even know, never mind care if the LPs they bought were sourced from digital copies rather than analog masters. But I have noticed that among the yougersters, LPs may be starting t lose a little bit of their "cool factor". And those who bought LPs because they were trendy will tend to stop buying them as the tend fades. It is far from dead, owning LPs as a high schooler just does not seem to be as important as it was a few years ago.
And on the other side of the coin is the aging baby boomers. While the article did site the availability of high res files as a factor in the decline of LPs, I think among those that are retired , or approaching retirement, the allure of files is often driven buy something else, the loss a space that can be dedicated to this hobby. As folks retire they often move out of the old family homestead and into a "retirement home." These home are usually by definition smaller in size which means that the space available for listening and storage of software may become limited. Moving over to a file based music server system is the perfect answer to that problem, as records and CDs can be stored on a hard drive eliminating the need to storage the physical media. A hard drive is also much less susceptible to damage from heat than say an LP, which could be a big deal to folks who are planning to head south to warmer climates in retirement.
So like I said, while I can't really disagree with much of what they said, I think their analysis is missing several very big reasons why LP sales are starting to ramp down a bit.