Why is this a surprise? They are corporatist, so their base hates them for betraying them. But the voters who are actually pro-corporate still dislike them because the Republicans are slightly more pro-corporate. Rich donor money has corrupted them into being Republican-lite. No one likes Republican-lite.
But the upper party power-players don't give a fuck. They are paid jobbers. They are getting rich being the Good Cop in a Good Cop/Bad Cop routine designed to advance corporate interests. They don't care that the country despises them for being a bunch of jobbers. They are laughing all the way to the bank. They get paid to job while in office, and if that jobbing causes them to lose an election, they just go to work as lobbyists for the people who paid them to job. Then, as soon as the Republicans Bad Cop routine makes them unpopular enough that people want to vote Democrat again, boom, they are back in office and its their Republican golfing-buddy who is in the paid lobbyist job.