Glad to see OP respond back and congrats to OP's success in the last ten years!
If I had to hazard a two-cent guess, I think someone like OP is not targeted due to lack of spending in key categories such as travel, shopping and dining.
For example, I have a good friend who comes from old European money but only has access to a trust fund that provides him with a fixed amount of cash per month. The amount isn't minuscule, but not outrageous by any means (think of it as an annualized salary of $300k or so). With that being said, he spends nearly the entire amount each month on things like dining at Michelin star restaurants, shopping at high end stores, buying J and F classes tickets to London, Tokyo, Hong Kong, etc. and staying the Four Seasons. He was charging all of this to a plain old Amex Green card and after about a year of spending, he got the Centurion invite.
He didn't even know that such a card existed, but he is quite happy with it these days because his personal Centurion concierge does most of his shopping for him and books him his travel stuff. He tells me all the time that the card actually saves him money because now his bookings get the discounted IAP and FHR rates.
