Maxperson
Morkus from Orkus
1)That's not a grapple. It's a horse trick. A grapple in d&d us forced.It's a classic horse riding trick I've seen in person.
They ride by, grab someone's hands, and pulled them up behind into the saddle.
2) the rider isn't trying to hold her lying down on thr ground to be dragged while also riding.
No matter how you slice it, that example doesn't apply. It's apples to my oranges.