Earlier quoted context omitted.
I only watched one game, but it seems that: 1) Yes, most games will end in stalemate. 2) Most wins would occur when one side has enough passed paws such that they chance upon promoting to a few queens. 3) The random-promotion significantly lowers the chances for checkmate. Promotion to a queen is so common that many players who play online chess set paws to automatically promote to queens, so they don't waste the 2 o…
There are only a few circumstances where you would not promote to queen. The first is if promoting to queen would cause stalemate. In that case, you would probably promote to bishop instead, because rook would cause the same problem as queen, and knight is harder to force mate with. In the rare case where a bishop would cause stalemate, you promote to rook instead. The second is if promoting to knight would force che…
By far the second most common piece to promote to is a knight, simply because a knight moves in a way a queen cannot. In my 10 years of playing chess, I have probably seen about 5-10 tournament games where promoting to a knight is the correct choice.
Here is a FEN of an example where the only saving move for Black is to play 1...e1=N+: "8/8/8/8/8/3K4/R3p3/3k4 b - - 0 1"
You are right in that the only reason to ever promote to a bishop or rook is to avoid stalemate, yet there is only one practical example of such, here: "8/2P5/8/8/3r4/8/2K5/k7 w - - 0 1".
White must promote to a rook, since if they promote to a queen Black will play 1...Rc4+, forcing 2...Qxc4, which is stalemate. I cannot even find a practical example of when promoting to a bishop would the best choice.