I guess the problem with CD-R is the short lifespan. It's not even about supposed cheapness or the fact that everyone can create one at home in 1-2 minutes, but the technical flaws. Total classics like some Strict or Atrax Morgue releases have just simply stopped working due to being "too old" and nothing more. As opposed to that, even tapes from the 80ies play just fine. So, my question is whether a CD-R is actually a real "music format" or just a temporary storage device (however, it would lose when directly compared to a flash drive or external data storage). Of course, a pro CD-R may look neat and professional, but well...
Of course, every further aspect of the CD-R image are a result of this. Larger artists often don't agree to CD-R releases due to the negative connotations, just like a published author wouldn't agree to stapled together xerox copies of his newest work. Established labels often don't want the hassle with malfunctioning discs. Also, real CDs aren't that expensive to press anymore, which was different during the CD-R boom, if I am not mistaken. So, probably, the bad image just stems from peoples' contact with the format. I mostly see young "Bandcamp artists" selling CD-R, which makes sense in a way, but on the other hand, maybe digital sales would be just as high, if there were no physical alternative...?