There are many more economists building on MMT than just them, at many institutions globally.

Describing the job guarantee/transition job as equivalent to "workfare" reveals a fundamental misunderstanding of the JG. Two ways in which it differs significantly (but not the only ways):

1/ it pays a living wage / socially inclusive wage, unlike most current (un)employment insurance programs

2/ it is non-coercive. You have the promise of that job, not a mandate to perform it. Other social programs remain available for those unable for for a variety of reasons.