I think the point is that the left dislikes Christianity, and sees it as the enemy, but for all the anti-Catholic stuff from the left, they also find more comfort with Catholics, interact more with and seek out Catholic leadership, confer with and seek out opinions from them, and often portray them positively and powerfully in news, media, and movies.
Evangelicals are merely mocked, marginalized, and attacked by the media.
Look at every story about Mormonism and Christianity, the media always reports it as ‘some Evangelicals do not consider Mormons Christians’ hinting that it is a backwards, fundamentalist, absurdity, you never see Catholics mentioned in that context.
The left will interact positively with liberals and negatively with conservatives. It will portray conservative Catholics poorly and conservative Protestants (Evangelicals) poorly. It will interact with liberal Catholics and liberal Protestants (such as Episcopalians) positively.
I don’t necessarily disagree with you that the left portrays Evangelicals worse than Catholics. That’s because Evangelicals are essentially conservative Protestants. but, while Catholics should be all conservative, there are still many liberals who identify as Catholic.
If all Catholics actually lived their faith and liberals were intelligent enough to notice, they would probably be hated worse than Evangelicals. While liberals like to mock how many Evangelicals hold the view of creationism, they would have an absolute field day with the Catholic belief in the Eucharist and the Catholic Church’s rejection of contraception.