Point understood, but I still say that there is nothing in the song, as sung by Lonnie Donegan (I am of course not talking here about the DT version, which is undoubtedly offensive), that can be considered offensive per se - it's only people's reading into it things it doesn't say.

Picking cotton is just an activity, and as such there is nothing inherently wrong with it. Just because people - black and white - have had to do it for a living, even under conditions of slavery, doesn't make the activity of picking cotton wrong in itself.

There were and probably still are jobs, even in western countries, where people are paid little for long hours of work. And there are plenty of songs about them.

I'm not accusing anyone of being PC, just suggesting they are perhaps being over-sensitive or reading too much into this song in the form sung by Lonnie Donegan, if they find it offensive.