I also thought the story of the woman who got a bicycle taxi to rush her to the gym was a fantastic point of irony to bring up. "Working out" is what we do now, instead of hard laborious tasks we, in previous times, had to do ourselves.
Also, bringing up Pres. Bush seems like Mr. Gopnik is seemingly making him the poster boy for what he describes as the "feudal class":
"...the thing about George W. Bush is not that he was born on third base and thinks he hit a triple. It is that he has been in a bicycle taxi all his life but has not yet bothered to notice that someone else is pedalling."