If that thread is heavy, then it will retain a lot of spring from the stiffness. But it is only Tex40, medium strength for buttonholing. Maybe it is bonded, the treatment reducing its limpness.
But, I've gone through bobbins full of Tex69 and Tex92 threads in a Class 15 home machine, without the problem you show, which looks like a spinning reel after a cast not concluded with a thumb on the reel. I've been lucky, or maybe sewing more slowly, or maybe winding the bobbins more slowly and smoothly than your sm does.