I think you guys are speaking in too much generality.
I agree that a lot of CD Players sound very similar and it's literally impossibly in blind tests to hear a difference. But there are players that have a certain sound, which can be heard.
I've done several blind tests with my Vincent CD S6 and my Rega Apollo and Rega Saturn, using the analogue outs.
I have been able to thear the difference between the three every time.
But the Rega players have a very unique, laid back......soft...organic....warm sound, compared to most players. And I am very familiar with them.
Just like with anything, at some point I believe there's a threshold of diminishing returns. I could never see myself spending $4,000 -$5,000 for a CD Player. I simply don't see the point.
I figure, if a designer/manufactor can't build a great sounding, high quality, well-built CD Player for under $2,500; then, it must be a fairly cr***y design. And the designer, not very good at what he/she does. And that's a generality, in itself.
But there are differences in sound, with some players. Differences don't always mean better, though. It's a matter of personal taste and what one can afford.