Scintilla? Perhaps more than that.
How about United States v. The William, 28 Fed. Cas. 614, no. 16,700 D.Mass. 1808, just 19 years after ratifcation?
"Further, the power to regulate commerce is not to be confined to the adoption of measures, exclusively beneficial to commerce itself, or tending to its advancement; but, in our national system, as in all modern sovereignties, it is also to be considered as an instrument for other purposes of general policy and interest."
Now, surely there were a few Founding Fathers alive in 1808 to say, "Hey, that's not what we meant!". Did anyone say that?
Are you saying that since Congress didn't exercise their power for 100 years that they never had that power? I hope that's not your logic or your argument.
Secondly, this is what I said: "There isn't a scintilla of evidence from the writings of either federalists or anti-federalists at the time that the purpose of the clause was to give the federal government any restrictive power over actual commercial transactions within the country." Your cite didn't contradict that. All it referred to were the end goals that particular measures were to shoot for, not the nature of those measures themselves.
Indeed they did.
James Madison to Joseph C. Cabell 13 Feb. 1829
Letters 4:14--15
For a like reason, I made no reference to the "power to regulate commerce among the several States." I always foresaw that difficulties might be started in relation to that power which could not be fully explained without recurring to views of it, which, however just, might give birth to specious though unsound objections. Being in the same terms with the power over foreign commerce, the same extent, if taken literally, would belong to it. Yet it is very certain that it grew out of the abuse of the power by the importing States in taxing the non-importing, and was intended as a negative and preventive provision against injustice among the States themselves, rather than as a power to be used for the positive purposes of the General Government, in which alone, however, the remedial power could be lodged.