I beg to differ.
Yes, some of them “jump as high as a horse” (Stroller won the silver medal at the Mexico Olympics, Grange Finn Sparrow competed successfully in the Open Jumpers in the US, and I know of several that competed successfully in Intermetiate and Advance Eventing- Hideaways Erin Go Bragh for one). And some of the very competitive ones can be “strong”.
But plenty of them are small (13h 2") and I know plenty that are PREFECT for “first pony or non-competitive kid”.