Amex has always been more premier in a sense. For Amex Centurion, as you said, its "don't call us, we'll call you". Meaning if you are elite enough, we would have heard of you and we would have already called you. If you need to call us to tell us who you are, then obviously you are not elite enough so diam diam.
The value of Visa Infinite cards have dropped somewhat. Now you can "express interest" and ask them to invite you. Which they actually do as long as you earn enough or have spare cash to invest in their FD or something.
Last time VI cards don't even appear on websites and they call you if they feel you are elite enough. No such thing as "express interest". But I guess times are tough and they are despo. CIMB even issues VI cards for a measly $50K FD! Even CIMB's so called "premier" VI card (so far only issued in M'sia) isn't that premier 'cos you just need RM 1 million (about S$460K?) in FD.
Its like Platinum cards I guess. Used to be elite but now almost every credit card, and even DEBIT card, says Platinum. Would love to know how the hell a debit card can be Platinum when a debit card holder doesn't even need a monthly salary!
And if a normal card requires $30K and a Platinum card requires $30K, then what's the diff?

Might as well upgrade everyone to Platinum. Or lower the minimum salary required for regular cards. At least there is some differentiation.
Even Visa Signature has little meaning these days. Its supposed to be one level above Platinum and one level below Visa Infinite. But some banks are pretty easy with issuing a Signature card.
I guess the most "terok" is Mastercard. Some banks like Citi and Maybank need at least $120K annual salary before they issue some sort of card that is World Mastercard. But banks like Stan Chart will issue you a Manhattan World Mastercard for just $30K. Well yes I appreciate the fact that I now hold a "premier" World Mastercard (round of applause) but seriously? Just how premier is it?
I personally am not after prestige or status so no issues for me. But to those who care, I guess the only card worth flashing is the Amex Centurion. The rest have diluted in status.