bdp24,
I think that all you mentioned together is the reason for CD sales decline. Probably with another thing or two. Times have evolved and, regardless of what anyone (hinting at your mention of Michael Fremer) feels and thinks, CDs and records do not fit into an iPhone. That is the dealbreaker. Those who grew up with some physical media may feel it is important to actually have it, but newer generations do not have that feeling.They do not have emotional attachment to these things. Similar approach is slowly getting into car ownership these days.
"Michael Fremer regularly talks about how those who get their music via streaming, owning no physical media, will end up with nothing."
Well, very "wise" statement that is slightly out of touch with reality. Even a physical one. What happens when there is fire, earthquake, burglary, basically anything that disturbs perfection of the environment, in "physically-inclined" home? Owner is easily left with, depending on the luck, nothing. 17-year-old who streams hip-hop on her phone is left with exactly same music as the day before.
Ok, burglary is probably fine. What would a burglar do with heavy load of objects of close-to-no-value to majority of potential customers? Records, and CDs, are not even worth stealing these days, no matter how much a small group of people may cherish them.
As far as Walmart goes, I put those few things out, and mentioned Garth Brooks, as a response to implied statement that Walmart never mattered in music (sales) and that people shopping there were not interested in music. Apparently, they were. It is just that they are not anymore.