You left out the most important factor of all: content. Imagine a game with the best graphics, music, story, and gameplay. It's over after 1 hour. Now the game is really disappointing. On the other hand if you have a super long game without much variety then that gets old too. Content is actually what people are looking for when they buy a game, both quantity and quality of content.
(You also left out challenge, but content is even more important.)
curl-6 bet me that PS5 + X|S sales would reach 56m before year end 2023 and he was right.
My Bet With curl-6
My Threads:
Master Thread, Game of the Year/Decade
Switch Will Be #1 All Time
Zelda Will Outsell Mario (Achieved)
How Much Will MH Rise sell?
My Bet With Metallox