Maggies Farm is a Dylan song from the 1960s.
it's probably about a commune. Communes were a scam: a trust owned it but really it was someone who ran it and people would come and work and leave soon after, so someone would basically let people be slaves for 30 or so days, and then haze them out of the place. Hence "i ain't working at maggies farm no more"
Thatcher didn't show up on the political scene till long long after.
The song was written too early to be about a commune.
here is an explanation of the song:
https://en.wikipedia.org/wiki/Maggie's_Farm
https://songmeanings.com/songs/view/108665/
this one is better than the other one and explains a bit more.
one theory: fed up about being tagged a protest song writer, he did a play on words and then made the song about something else, which was his right.
He was protesting the idea that he had to be a protest song writer, is one of the theories.
Hey, Mr. Pig, they try to frustrate you and play 'whack a mole' with you as their target.
but you're a cat!
they never can get to you!