For the demographic FB cares about, yes they lean left (which is what I am assuming you are getting at, and I agree with you that most of the time it's safe to just do left leaning PR). But Target openly supported bathroom access rights (left leaning) and have been met with a huge backlash from many right leaning markets which has materially impacted their bottom line with defections to Walmart and ecommerce.

It's not automatic who you need to PR for.