This isn't even true tho. Cory Booker (black) is still in the race, and Buttigieg (mid-30s) is not that rich. Few of them are even remotely close to Trump in wealth, except Steyer and Bloomberg.
Many women ran in the primaries, and some are still running, one of whom is still a top-tier candidate (Warren).
The 2020 Democratic field has been the most diverse presidential primaries ever, by a long shot, and it is really rich for the GOP to accuse us of lacking diversity when you guys are led by a walking embodiment of old white rich privilege.