The Bills looked strong throughout at SoFi Stadium, with quarterback Josh Allen putting in a sensational performance as he threw three touchdowns, rushed for one of his own, and completed 26 of 31 passes for a total of 297 yards.
After unveiling their Super Bowl LVI banner, the Rams struggled in front of their own fans as all 10 of their points came in the second quarter, with Buffalo shutting them out in the second half.
"When you look at a lot of the ways that this game unfolded, [I] feel a huge sense of responsibility to this team," McVay said after the loss.
"We weren't ready to go. I take a lot of pride in that, and that's on me. I've got to do better. There were a lot of decisions that I made that I felt didn't put our players in good enough spots.
"So it was a humbling experience, but we're going to stay connected. We're going to all look inward. We're going to do a better job moving forward."
Allen became the first QB in NFL history to record 250+ passing yards, 50+ rushing yards, three or more passing TDs, a rushing TD, 80 per cent completions and a win in the same game.
Speaking to NBC after the victory, Allen said: "We knew if we came out and tried to execute the way we know we can execute, we were going to move the ball the ball and score. Our defense played a hell of a game.
"Defense's job is to get the ball back, but the offense can help and let them go and pin their ears back by getting up and putting them in legit passing situations and letting them go.
"We got a bunch of dawgs up front. [Former Ram Von Miller] is the leader of that D-line and they played outstanding."