It's no more unenforceable than GPL is unenforceable.
But MIT + weird condition is radioactive to anyone who takes licensing seriously.
Might just as well write "for hobbyist use only".
It is more unenforceable since the LICENSE file in the repository clearly states that I can "deal in the Software without restriction", and that includes the right to "sell copies of the Software".
It is more unenforceable since the LICENSE file in the repository clearly states that I can "deal in the Software without restriction", and that includes the right to "sell copies of the Software".