Except those people who have "mediocre soundbars" can't afford buying a $3.5K VR headset. And those who have a spare budget of $3.5K to enhance their TV watching experience will invest the money on a better TV and a surround speaker setup.
Also not everyone lives in a house, I’m sure Manhattan condo owners can afford the price of the theatre gear, but cannot afford the space required for them to be used optimally. Wealthy people don’t all live in mansions.
There are many many people for whom money is not the limiting factor. It's because they don't have the space, the technical wherewithal to set it up, the motivation to make it happen, or some combination of all three.
can't imagine people will only be buying it for movie watching.