One of the problems facing the Fritz player in the 8...Ne6 variation, is that he has to make progress. Little progress can be demonstrated in the 11...Be7 line and White just holds the pawn. The 11...f5 variation underscores one of the chronic problems facing Black---an inferior endgame. The old timers thought that a pawn majority on the Queenside was close to winning. Here, White just transitions to a slightly favorable middlegame with the only side with any real chances to achieve a plus in the position. He has three plusses: 1)Better pawn structure, 2)Good prospects of creating a passed pawn on the Queenside, 3)The undermining move b4 going after the support of the passed pawn on d4 will be a recurring threat. Together they point to a significant long-term advantage to White.
Ask any Grandmaster, "Which would you prefer to play, White's position or the Black position?" I predict that the overwhelming majority of players would prefer to play White. Also, there is no requirement to give up the pawn, but White's prospects are excellent here. Perhaps other post readers can figure out ways to shut down the attack and still keep the pawn.
11...Be7 is the main line from my understanding and black is doing fine.