This article summarizes tax on wireless services and the total is about 17%, with 12% state and local charges. And that varies from state to state, city to city. It also includes charges unique to phones, such as 911 charges. Whatever the case, each government, Feds, FCC, state and local, would vote to extend those taxes to internet and what they decide could be 0% or 40% or any value imaginable.
Bottom line is this is the kind of dishonesty in evaluating the proposal I expect from the right wing, which is why I have to look elsewhere.