America fought against classism and aristocracy and in the Gilded Age heiresses were wearing crowns!
They wanted to be Brits! Yuck! I am glad the wealthy started to invest in American art in the 1920s. Porgy and Bess. Norman Rockwell. Grant Wood. Edward Hopper. Frank Lloyd Wright. And Native American iconography. This is more American.
Not cheesy hammy faux Princesses like Ms. Vanderbilt. Tacky fussy Americans pretending to be nobility. Interesting time.
Why did rich Americans like British pomp in the Gilded Age?
Rich Americans saw themselves as American nobility. Some of them, Vanderbilt's for example, as you mention, actually married nobility becoming members of that part of British society. Many of them hired high priced genealogists to travel to England and Europe to dig up noble ancestry and coats of arms to brag about. Most of which were actually faked. The answer to your question is actually in your question. They wanted to be noble or special and bought their way in much of the time. In fact British laws were changed to protect actual noble houses from being sold off to wealthy Americans.
These things are cyclical, and happen in the middle classes as well. I grew up in the 1980s with what was called, musically, "The Second British Invasion", a reference to the first one of that sort in the mid 1960s:
Americans are British, the independence war start whit "no taxation whidou't reprezentation". Is because UK didn't let them considerate themself true brithish.
i'm not a native English speacher. I whrite moust of the time in the way my language do. I don't have roul of writing in my language witch is more simple
I'm saying I liked the wording of the question before looking I wanted to see female in profile instead of male. But if you don't understand what I'm saying then maybe I was off in the very first place
