A brief follow-up to this: apparently Michael Barr has withdrawn from consideration for a seat on the Federal Reserve Board of Governors. All it took was making the White House’s interest - and progressive opposition - public, which means it was pretty precarious to begin with.
The financial reform coalition has definitely amassed some political power, if they can stop nominations in their tracks within 24 hours. Whether that translates into meaningful change over time remains to be seen. Meanwhile, the seats remain vacant, and the White House has certainly not indicated that they would be likely to give in and nominate an advocate for breaking up the banks (although it’s worth noting that Daniel Tarullo, the current point person for financial reform at the Fed, supports a cap on bank size).