They dont do abstract manipulations. They dont do the "3 + ? = 10" and therefore "10 - ? = 3". Teaching algebra means teaching abstract manipulations too, like 2x+4=10 and therefore (2x+4)/2=10/2 and therefore x + 2 = 5 and therefore x=3.

The thing you wrote here does not count as teaching algebra. It is just one preparatory step and has nothing to do with delaying algebra or not.