I'm sure you'll agree that a motivated and determined bad actor can steal anything, at best you're looking for a better deterrent.
Having said that, and agreeing based on experience that the common locking pins are relatively easy to defeat with applied force (I 'popped' one off for a friend who lost the keys), I note this is now available:
https://www.provenlocks.com/products...lock-model-hl1
Nope, I've no idea if it's actually any more resistant to 'forced removal' than other less expensive alternatives.
Maybe someday the folks at
Ft Knox Locks will come up with a truly hard-core receiver lock.
Good Luck!