Yes, the inertial and gravitational mass are the same. Think of a little ball with layers spinning opposite directions, just s we don't even have to think about angular momentum. It's got some inertial mass that you can measure. In a gravitational field, it will drop just like anything else. If the gravitational mass ere different from the inertial mass, it would not drop at the same rate. We'de have a way of detecting a uniform gravitatinal field. That would violate the equivalence principle, which has been well confirmed by all the confirmations of General Relativity.
Mike W.
(published on 07/30/2020)