If you look at how the phrase is used in conversation, you can see it has nothing to do with the song Billie Holiday made famous, except for containing the words “fruit” and “ hanging“. The phrase refers to the easy parts of a long and difficult task. For example, If we speak of the difficult goal of providing free college education for everyone, we might speak of Biden’s cancellation of student loan debt as “low-hanging fruit.” It’s something which won’t solve the entire problem, but it will solve part of the problem, and is relatively easy to do because new legislation doesn’t have to be passed. It’s a reference to the fact that if you are picking actual fruit, it’s easier to pick the low hanging fruit, because you don’t have to climb up into the tree to get it. It also implies that the rest of the fruit still has to be picked, so you can’t say the job is done just because you have picked the low hanging fruit. None of these implications make any sense if this phrase is referring to lynched human beings.