What from the US counts as forced labor?

If you’re going on about prison workers, that’s not going to count. They are paid for it. Not much, which is another issue. But they are paid for it, and they do not have to take a job if they don’t want to.

On top of that, most stuff produced by prison workers in the US is basic office supplies used in government facilities.

Some companies do have programs where they hire prison inmates, but again, they’re voluntary jobs, and the inmates are paid.

As a more philosophical question, what do you want inmates to do in prison? Would you rather have them just sit there, or possibly learn some skills in manufacturing that are going to get them a job when they’re out?