I don’t see why you would need that much space nor a real horse. This is intended to be virtual reality after all. While such a simulation isn’t for everyone, it does allow you to simulate better the idea of the “fog of war”, the problems of communication and coordination in a bygone era, and mass troop tactics and strategy.

A lot of VR activities wouldn’t require a large space. Racing the Tour de France on a stationary bike would just require room for the stationary bike.

Now, directing the Prussians at Waterloo – that might require a few acres and a horse to do it right. You’d want to carefully augment reality there – you don’t want to be completely cut off from the real world if you’re really on a horse.

Pitching and batting would work well in the gym described. Looking at the dimensions, it looks like you could fit the pitcher’s mound, homebase, and even first base in an 18 meter square facility (you’d have to do it diagonal). A full game of baseball would require a baseball field – unless you had Star Trek holodeck technology. That technology would allow you to simulate large spaces because it would always be moving you back to the center of the room. Trickier was how it would allow others to interact with you in that space. Some guy that’s only a few feet away could be made to seem like he was miles away. Now how was that supposed to work?

I’m sure the producers of the show would answer, “very well, thank you.”

Also, you could really do some fun stuff with a semi-stationary bicycle with this kind of a garage.