Why do Some British Actors Improperly Dismount Horses? 🏇🐎

Here's a British actor properly dismounting a horse, from  Victoria Se1Ep1:

Conversely, here's Rufus Sewell, as Lord Melbourne, improperly dismounting his horse:

What if the horse reared up its head and your spurs hit its neck? The horse might bolt causing injury to mount and rider alike.

Here's a wiki and youtube instructions for all to learn:

Obviously, both John Wayne and James Caan learned how to dismount horses properly in "El Dorado"

Richard Cumberbatch also properly dismounts, hunchback and all, in Richard III