The prevailing argument against regulation is usually cost. "It would be expensive to implement this! MILLIONS OF DOLLARS!" and to the uninformed outsider this has a ring of truth to it. However any cost figure would be largely overstated as facebook and other big providers are already complying with European data laws. As such the fundamental architecture and implementation have already been done for a non-trivial segment of the internet population. All it would really take is rolling out that infrastructure to the US. Not to say it would be a completely painless process, but they already established a lot of knowhow.