By Chris Rosvoglou Sean McVay has been awfully successful as the head coach of the Los Angeles Rams, but San Francisco 49ers head coach Kyle Shanahan might just be his kryptonite. The 49ers managed to defeat the Rams both times during the 2021 regular season. The second time around, the 49ers managed to erase a 17-point deficit on the road en route to a playoff-clinching win. On Sunday, the 49ers and Rams will meet in the NFC Championship Game. It’ll mark the third time these two rivals play each other this season. When speaking to reporters on Wednesday afternoon, McVay was asked if Shanahan …