Subtract value from list

I would use Clip:

Clip[{2,3,5,4,6,7,3,7,5,4}, {5, Infinity}, {0, 0}]

{0, 0, 5, 0, 6, 7, 0, 7, 5, 0}

You could also use Threshold

list = {2, 3, 5, 4, 6, 7, 3, 7, 5, 4};

value = 5;

For the case of integers

Threshold[list, value - 1]

(* {0, 0, 5, 0, 6, 7, 0, 7, 5, 0} *)

EDIT: Comparative timings

kumar[list_, value_] := UnitStep[list - value] list

hanlon[list_, value_] := Threshold[list, value - 1]

alan[list_, value_] := If[# < value, 0, #] & /@ list

woll[list_, value_] := Clip[list, {value, ∞}, {0, 0}]

nasser[list_, value_] := 
 ReplacePart[list, Position[list, x_ /; x - value < 0] -> 0]

{#, RepeatedTiming[Do[temp = #[list, value], {10000}]; temp]} & /@ {hanlon, 
   woll, alan, kumar, nasser} // Grid

Using UnitStep

UnitStep[list - value] list

{0, 0, 5, 0, 6, 7, 0, 7, 5, 0}