I'm not sure it will make them more partisan. It will make them be seen to be more partisan. Once you're dependent on somebody other than yourself, whether you're dependent on Facebook, on Google, or on the government in power.... Let's face it, governments do change and the people who today think the media is toadying up to the Liberal government will at some point in the future believe that they're toadying up to somebody else.
It doesn't really matter whether they are or not. What matters is that people won't believe them.