Seattle Seahawks quarterback Geno Smith accused New York Giants linebacker Isaiah Simmons of dirty play in Monday night’s win, but the discipline handed down over the play by the NFL makes it clear that the league very much did not agree.
Smith was fined $10,927 for unsportsmanlike conduct for confronting Giants players after the play, according to Tom Pelissero of NFL Network. Simmons himself did not receive any discipline for the tackle.
The NFL didn't fine #Giants LB Isaiah Simmons for the tackle that temporarily sidelined #Seahawks QB Geno Smith on Monday night, but did fine Smith $10,927 for unsportsmanlike conduct — barking at the defense after he returned to the game.
— Tom Pelissero (@TomPelissero) October 7, 2023

Smith was angry during and after the game, openly accusing Simmons of dirty play and suggesting that he hoped the league would take action against the Giants linebacker. A certain amount of frustration is understandable since the tackle briefly forced Smith from the game due to a knee injury, though he did return later.
Some saw Simmons’ tackle as a type of play that may be banned in the future, but for now, there was nothing illegal about it. The league’s discipline reflects that, though Smith is highly unlikely to be happy that he was the only one fined for the entire sequence.