"The problem, he argues, is that the standard is based on applying a small flame to a bare piece of foam — a situation unlikely to happen in real life. ... In real life, before the flame gets to the foam, it has to ignite the fabric. Once the fabric catches fire, it becomes a sheet of flame that can easily overwhelm the fire-suppression properties of treated foam. In tests, TB 117 compliant chairs catch fire just as easily as ones that aren’t compliant — and they burn just as hot. “This is not speculation,” he says. “There were two series of tests that prove what I’m saying is correct.”
The problem is that the government has decided that you shouldn't be able to make that decision for yourself - laws require that couches be sold with retardants. Arlene Blum managed to commission a custom-built couch without fire retardants, but that's neither scalable nor viable for most people.
I don't know whether the claims in the article are well-supported or not (or what type of treatment the couch in the video had, as the videos are from the late 80s/early 90s), but I think most people don't realize just how dangerous a working fire in a single room full of ordinary furnishings can be.