No. People like this are missing the point. Linehan is the play-caller, but he operates by Garrett's philosophy, which is why his offense doesn't look that much different than the one Garrett ran. Linehan just added some twists to Garrett's playbook, but it is Garrett who believes that we have to line up and just outexecute the other team.
All it takes is looking at the Rams to see that execution and creativity hand-in-hand make an offense elite. Firing Linehan won't fix Garrett unless Jerry forces him to bring in a creative offensive coordinator and let him have complete control over the offense.
This is the same tired offensive lack of creativity we've seen from Garrett since the team hired him.