The use of thou indicates singular man, does it not?Cat among the pigeons, aren't most of the men (homo) responsible for the faults commented on in the hymn also men (vir)? Being in the position to take the decisions which waste the earth - I'm sure that women in the same place would not be innocent.
Can we go back to calling men weremen? since that is the derivation from the original, where man (homo) was modified into wifman (femina) and wereman (vir). somebody decided that men (vir) were the base state and didn't require differentiation. Without that, it would be true to use man as inclusive.
This is one of the hymns where the poetry is so good that it seems very wrong to change it. I've seen a dire rewrite of Dear Lord and Father which loses the rhyme scheme and the sound effects in its eagerness to abandon possible gender problems, and substitute the impersonal you for the personal thou (in verse by a Quaker, who used thou in everyday speech).
Penny