The straightening properties are real
This stuff is great for blowouts! It isn't so strong that it's hard to leave some curl or wave to my hair, it just makes a smooth blowout easier.
I have type 3A (or so) curls with a fair amount of porosity. I wear it straight a fair amount of the time because getting it to look nice curly is harder than it seems but if it's straight I can go several days without a wash or even a restyle.