True. The em field is significantly more energetic, meaning that it contributes more to the stress energy tensor than the force of gravity

But recall that the force of gravity is the momentum change “due to” the curvature of spacetime. The fact that the force of gravity can bend spacetime at all is a really weird second-order perturbative effect.

These perturbative effects are typically described with a quantum field theory, but gravity has been thus far notably difficult to quantize.

It does. The energy density of the em field will contribute to the stress-energy tensor that changes the metric of spacetime.

Though the force itself is irrelevant