I still see it as nerf for fighters. Currently in 5e an 11th level fighter can make 3 attacks and move, all others (with extra attack) can make 2 attacks and move.
Your suggestion removes the movement from the fighter. The fighter is basically stuck in place. So you have all other classes with extra attack can make 2 attacks with no penalty and can move (just like 5e but with less movement) and the fighter can make 3 attacks with no penalty, but no movement (which is a downgrade from they can do in 5e). Not to mention if the non-fighters get advantage (or a bless) they can essentially act like a fighter which means they are more versatile.
Shoot, I actually did forget about movement. Whoops. Maybe fighters at level 5 can attack twice with one action once a turn. Hmm, need to think on that some more. Or maybe I find another way to boost fighters damage and accuracy outside of attacking more. Back to drawing board.