After this past election cycle I don't see how people can make that comment with a straight face.
Media in general is very right leaning. Some like CNN and NYT are maybe slightly more left than far right fox news, but there aren't many "left leaning" mass market news sources that are essentially felating one party for millions of people.
NYT and CNN, etc are all very critical of democrats when there is a controversy. This is stark contrast to fox news which essentially is willful ignorance of anything bad republicans / trump has done.
The "normalization" of Trump's corruption by media in general should be enough to see which way they lean.
Its just that if anybody is slightly less than full blown fox news conservative they get labeled as left leaning by everyone in the media so there is some idea of "balance" but conservative media (fox news, conservative podcasts, etc) are overwhelmingly mass market and the majority.