Units: speculation, rumor, slander and silliness

[Nelson]

I know this pedantic of me, but dragoons are mounted infantry not cavalry.

When first introduced in the 17th century, yes. But like grenadiers, their original function became obsolete. By Frederick the Great's time dragoons were almost exclusively employed as cavalry and invariably referred to as such.

It makes sense. There was plenty of infantry around. Dismounting the dragoons would have wasted them.

[Sol Invictus]

Besides, who wants to fight as a poor bloody infantryman when you have a valiant steed at your call. Much more glorious to take part in a Cavalry charge than to slug it out with a carbine.