US legislators have almost no say in how schools are run. The DoE is a husk, and states call the shots. In my state of Oregon, you will have wildly different curricula and standards depending on your district, because there's almost no state oversight either.
To be fair, the US has long followed a model prioritizing district-level control, this isn’t anything new.
Yes, that is what impotent means.
They made a choice - US legislators effectively gave up their control of how schools are run when the conservative coalition allowed the trump administration to dismantle the DoE without congressional approval. Congress itself could legally retain control of education, but if congress refuses to assert that power then it is meaningless.
The end goal is to dismantle public education and route public money to religious and private schools.