and not representative of most D&D games IME
Has anyone said it
is representative of most D&D games?
I have no clue why people would watch
others play D&D when they could play themselves.
Possibly similar reasons why people watch televised sports or gaming streams. Plus, of course, in this case you also have the possibility of people being fans of particular actors who are on the show and want to watch them. There are many reasons why people might want to do something that you personally don't want to do, after all.
INSHO if you have time to watch CR, you have time to play D&D instead. Yeah, I know, people are busy, they can't find players, etc. Crap IMO. You think it is hard to find and organize a game now?
There are
so many assumptions built into this, both about how people play D&D and about how people watch CR. Someone had already pointed out before your post that they like to put CR on when doing some other activity, such as exercising. You can't play D&D "in the background" like you can put a show on in the background while doing something else. Meanwhile many people strongly prefer to play D&D with their friends. If their friends are not available, they prefer to do something else rather than play with strangers. Again, people often have different preferences than you do.
Try it in the 80's before gaming, video games, anime, comics, and such things were NOT mainstream in any way, shape, or form. To be clear I am not saying finding a game or group is easy, but you can do it if you really want to IME.
Plenty of people who watch CR do have an active D&D group. That doesn`t mean they can all drop everything and play D&D whenever. So here`s another tidbit: you can both be playing in an active D&D group
and also watch CR when not actually gaming. Two of the players in my group watch CR, the other five (myself included) do not, for example.