This is false seeing that factors that go into in game play compared to a SIM a in game experience
First off, stamina is handled incorrectly if you change the period length compared to how they SIM (if you keep generic sliders then the first line plays a solid 8 minutes in game time before a line change by the AI), which affects time on ice stats and player growth, however SIM games seem to have more evened time on ice, then there is how penalties are handled whereas a simmed game has proper numbers for penalties compared to an in game experience where they are barely existent, then we can look at possible injuries (especially goalie) seeing that if you SIM they are possible and can affect the outcome of games whereas if you play games there is no coding for goalies injuries at all.
This doesn't even go into the animation based gameplay that can affect in game users (you poke check the puck away from the AI, moves towards center ice but then morphs back to the AI stick).
It's not about the computer picking wins or loss but how inconsistent they are from eachother.
How often do you play offline?