Here's what I'm throwing out to see if it jives; he loves marrying women with accents, he craves McDonald's, he's a big shot in NYC and the upper crust is where he lives...who is it? If you think Trump, sorry I'm referring to Carrie's long time on-again/off-again fictional love interest throughout the Sex and the City series.
There was a time back in an era long since past when the now President Trump was not thought of as the embodiment of a conservative as he is today. As a matter of fact, he was a well known New York top dog during the time the series was pitching Carrie and Big as an item. Put these thoughts together and Carrie being a lovelorn Trump admirer might have been a plot that took a different kind of turn when you view it in today's context.
The writers of Sex and the City may have loosely based Mr. Big in some ways off of Trump at the time or at least referenced some of his mannerisms as total opposites attract for the Carrie and Big dynamic. Either way, I'm pulling up a chair and re-watching the series to dig into the slightest support for my theory because why not? Carrie and Big are a story that deserves to be revisited and spark multiple fan theories. The writers did their work on making two extremely different characters believable as the "will they/won't they" of a generation. Plus there's always room to wonder if they would have truly lasted in the climate of today.
My prediction of their fate would be this; Carrie and Big divorced around the 2016 election. It would have been a sad "The Way We Were" type of end for the two, with an occasional fling here and there for old times.