They are, in the context of F=ma where m is the inertial mass and an object is deviating from a spacetime geodesic, which explains why we feel a force from gravity as we sit here.
Do you feel a force from gravity? I thought you feel the electromagnetic force (normal force) of your chair pushing you away from the Earth and stopping your free fall.
If not for the gravitational force, the normal force would have nothing to exert. So I guess you feel the magnitude of the force from gravity via the normal force.
Well, if you are currently at rest in relation to the surface of the earth, that means you are moving with speed c towards the future (the ct direction in Minkowsky space time). The shortest path from the past to the future, near a large mass like the Earth, is curved towards the center of the Earth. So, because of inertia, your trajectory in spacetime will be curved towards the center of the Earth. However, the surface you are standing on is preventing this motion via an electromagnetic interaction.