U.S. Constitution, Article I, Section 9, Clause 5.
This provision prohibits CONGRESS from imposing taxes or duties upon export from a state. It does not prohibit the state taxing exports. Regardless, this not a tax on an expert; rather it is a tax on a purchase.
The power to regulate this falls to Congress, not the states, not SCOTUS and not POTUS
Article I, Section 8, Clause 3:[3]
[The Congress shall have Power] To regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes;
True enough. Thanks for the correction. The clause I cited was a Federal tax issue.
But the following IS a state tax issue.
“No State shall, without the Consent of the Congress, lay any Imposts or Duties on Imports or Exports, except what may be absolutely necessary for executing it’s inspection Laws: and the net Produce of all Duties and Imposts, laid by any State on Imports or Exports, shall be for the Use of the Treasury of the United States; and all such Laws shall be subject to the Revision and Control of the Congress.”
U.S. Const., Art. I Sec. 10, Cl. 2.
If Congress has not passed a laws regarding internet taxation between states, SCOTUS is on shaky ground.
Not only that, the SCOTUS decision even if constitutional, only applies to the parties of the case and any other case with the same questions of laws and fact. Congress and ONLY Congress, not SCOTUS, is authorized by the Constitution to make national law.