Of course its being PC since this is exactly how PC is defined. You don't get to wish away the label simply because you don't like it, especially when you've just repeated the definition.

I can always tell when I'm talking to someone with a strong filter and it always makes me feel uncomfortable. They don't seem genuine, they don't seem honest, they don't seem real. I wonder how they are really like when relaxed with their filters down. What if they really are a douchebag? I've met plenty of people who filter heavily but are still basically sociopaths.

I've heard there is now corporate training on how to have a strong filter without letting other people know that you have one, by intentionally and strategically letting out noticeable but forgivable gaffes at certain points to make it appear as if you are genuine.