You made my own point against yourself — his mindset was unconstitutional and Jefferson got the funding by making it look like a minor matter, a matter of understanding the “details” about the land to be occupied.
We haven’t yet seen any “science amendment” to the constitution. Now when one comes, then you have a conservative, constitutional leg to stand on.
I actually agree with you on the Constitutionality aspect, but history has proven repeatedly that the current approach to funding of research is NECESSARY for national survival, both military and economic. A "pure market" approach simply doesn't work as well.
And most of the abuses are the result of "avoiding competition" (crony capitalism or a monopoly on control of funding).