and where is the objectivity in this domain?
Good question. There's little to none. My conclusion is if it's not blind, they didn't hear it. The only time I would pay any attention whatsoever to a subjective review is if that person continually came to the same results as I.
Regarding #2, you'll usually see an influx of items for sale when the next "hot" thing comes out. The herd is always chasing the newest rabbit. Doesn't necessarily mean people are dumping them for cause.
Regarding #3, there are plenty of technical articles showing why MQA is just a money-making scheme.
BTW, there have been blind tests on SACD, including an AES paper. I think you can guess what the results were. However, there was an audible difference in the noise floor when there was no signal and high system gain at a level where music would have been "unpleasantly loud".