I'm familiar with Graeber's work. His latest book on "Bullshit Jobs" is on my current reading list.
I would just say that "full-employment" is a relative term. It means that everyone that wants and needs a job can find one. I'm also an advocate of universal basic income and of transhumanism. I think that everything that can be automated should be automated and that the necessity of work should be eliminated over time.
One thing to note about the job guarantee proposal, as put forth by modern money theorists, is that it only works as planned if the new jobs are all productive jobs rather than bullshit jobs. According to MMT, such a program will not cause inflation if, and only if, it increases the nation's wealth proportionally to the government spending involved. So, the new jobs need to be productive jobs, preferably focused on improving infrustructure and advancing green technology.
To be clear though, the job guarantee is just a bandaid, not a solution.