Why didn't Nintendo make more realistic, violent games for the Wii just to prove 3rd parties wrong?

[menx64]

I think nintendo didnt really see the importance of those games but until a couple of years ago. I am sure they could make an amazing COD clone or some gears kind of game, but I believe, they know making those games wont change the perception third parties have of them. Lets imagine for a second nintendo makes their own assassins creed, halo, gta and gears games and they sell around 1-2 millions each.
Nintendo: Amazing, third parties now can replicate our success with their own games!
3rd parties: Look at nintendo coping our games! Now nobody is going to buy our games because everybody is going to be waiting for their sequels!!!!
N-Fan: Ok, those games were ok, now where is zelda,fzero and metroid??? Reggie???