Ok I guess you didn't see my equations

Force=mass x acceleration
acceleration= force/mass
Substitute for force you get acceleration=mass x acceleration/mass (a=mg/m)
Giving you a=g which is the gravitational constant

This is true for two objects with with same coefficient of drag.

And you are right, this isn't a new problem, it's been known for a long time that gravitational acceleration is independent of mass, given the same coefficient of drag.