I think this is a cool project, but yeah of course they're stretching the definition a little bit. "Backpack powered laminar flow propane torch" doesn't get you 12mil views on youtube.
At 4000 degrees Fahrenheit, would the flame's fuel gasses technically be a plasma?
And if so, then what's the detail that made both of us think that what they built doesn't match our expectations? Maybe we assumed they'd say "flame" for this design, and only say "plasma" if it was a cold plasma?