What it is
The opinion loophole is how a falsehood or a scam slips past criticism by filing itself under protected categories: “that’s just my opinion,” “it’s my belief,” “free speech.” Once something is labeled a belief, questioning it starts to look like an attack on the person.
Opinions deserve respect. Claims about facts deserve checking, whatever they call themselves.
How it shows up for me
I’m careful here, because I want people to keep their right to believe strange things, including me. But a fake cure sold to a sick person isn’t an opinion. The test I use: does it make a factual claim someone could lose money or health over?