It's a logical extension of the parties being so far apart. As long as there are legions of voters that will vote in step with either party no matter the candidate, snafu, or uncomfortable association, there is no incentive to push for less corruption.
This was kinda the big issue for chunk of Bernie supporters, so moves like this are not so subtly saying that their votes are not a priority for the Clinton campaign.
For full transparency, I voted for Sanders in the primary (and Obama in 08), but I am voting for Hillary this fall. Can't say she hasn't made a colossal mess of what was supposed to be a cakewalk.
I think to kind of piggy back on your thought, we may be seeing a shift where more is getting done behind closed doors than it was historically, specifically because there is so little concern about pissing off the base. No sane Democrat is going "I hate Hillary so I'll go vote for Trump". As a result there's more power in getting things done in the backroom, because there's less worry about voter backlash.
There was a time this was done with Pork in bills, and it made it so the parties could work together. Frankly, that was preferable and was at least more transparent.