After watching game 12 it is clear that neither of these players is of the standard we have seen in the past few decades that I have followed chess.
People ask about if Fischer was playing now, and maybe Fischer's opening preparation wouldn't be as good as those of modern players, but assuming he'd get through the opening, the middle game is everyone for themselves and Fischer would not have gone from a won position to a lost one. Nor would Carlsen, Karpov or Kasparov.
Having studied the Fischer vs Spassky games, Fischer did of course make a move that lost the bishop for 2 pawns in the first game, which whilst not technically lost at that point, was to me a clear blunder, and the only other clear blunder he made to me was in game 15 which he had won and let slip away. Spassky made 2 clear blunders to me, in games 5 and 13.
The rest of the games was mostly Fischer simply outplaying Spassky, or the other way in game 11.
None of those went from a won position to a lost one.
People ask about if Fischer was playing now, and maybe Fischer's opening preparation wouldn't be as good as those of modern players, but assuming he'd get through the opening, the middle game is everyone for themselves and Fischer would not have gone from a won position to a lost one. Nor would Carlsen, Karpov or Kasparov.
Having studied the Fischer vs Spassky games, Fischer did of course make a move that lost the bishop for 2 pawns in the first game, which whilst not technically lost at that point, was to me a clear blunder, and the only other clear blunder he made to me was in game 15 which he had won and let slip away. Spassky made 2 clear blunders to me, in games 5 and 13.
The rest of the games was mostly Fischer simply outplaying Spassky, or the other way in game 11.
None of those went from a won position to a lost one.