Why can't we drink wine that was made by a non Jew but was made from beginning to end by machine? Needless to say that according to the Gemara that it is only yayin nesech, if the non Jew makes An actual libation with it. Even if you want to call it yayin Stam, according to the Gemara it's only yayin Stam if the non Jew touches it after all the wine has been stored in the barrel to ferment. Since before it is put in the barrel it is unfit to drink or be used for a libation.