Should it matter? You can analyze this disparate piece of evidence independently of the agenda. In fact, you might even say that by putting the cards on the table, at least this source is transparent about which stance of the topic it is taking, giving you opportunity to take care when evaluating single pieces of evidence.. this is possibly better than sources which purport to be fair and balanced and go to greater lengths to obfuscate ways they are tacitly pushing an agenda.

I don’t agree with the concept of forming a high-level conclusion about the general nature of a source of information, and then using that to argue that you should not separately carefully analyze disparate pieces of content from that source.