And that's why YIMBYs like me like to call the leftists who oppose building more housing "fauxgressives."

  ...oppose development, it's mostly upper middle class whites

Wait for it...

  53% of whites (*support* building more housing)

Your own quote literally belies your claim. A valid conclusion from that source is that "whites support more housing but at lower rates than (other ethnicities)", but that's not opposition.

Huh? The claim was that the people who oppose development are predominantly upper middle class whites, not that a majority of white people oppose development.

"belie (trasitive verb)

1 a : to give a false impression of: "Her gentleness belies her strength."

b : to present an appearance not in agreement with: "His manner and appearance belie his age."

https://www.merriam-webster.com/dictionary/belie

To say "it's mostly upper middle class whites" does give a false impression of what the study said.

Do you have other sources that support that statement?

But the chosen quote doesn't support that claim.