Also from the Wikipedia you quoted
By an interesting coincidence, this folk-melody was also the first utilized by (Martin) Luther for his German chorales. He set it to his “Nun freut euch lieben Christen gmein <em/>
<b> Which is forbidden according to many Poskim. See Mishna Berura and Biur Halacha on 154:11 </b>
Obviously its allowed since almost all of us use that tune