If I have a 400V capacitor with a ripple current rating of 2.2A, if I drop my voltage to 200V am I safe to now ripple 4.4A?

I am only considering the ESR power dissipation in these ripple current limitations.

 

No you are not safe because the ESR is still the same and the power dissipated by it won't change because the ripple current stays the same.