Yes, the Bills cannot expect to win a game with five turnovers.
Yes, the OT interception was an interception.
Yes, the Bills got jobbed on a DPI called against them at the end when a very similar DPI was not called against Denver with a Bills player in the end zone.
I understand the sentiment for a 15-yard DPI, but this would just lead to DBs mauling WRs downfield. I think the only solution is to tell WRs that if a DB has played you well enough that he is in your hip pocket, he can hand fight you all he wants short of wrapping you up. No flags for hand fighting. No flags for face guarding. Only flags if the DB has his arms wrapped around the WR’s arms before the ball arrives.