Are you unable to make a distinction between administrations? When Eric Holder was AG, he claimed to be Obama's "wingman." The two of them were ideologically eye to eye.
When Trump was sworn in, all of the sudden the DOJ was supposed to be "independent" according to Democrats, RINOs, and the media. The majority of the DOJ leadership worked to hamstring Trump as it was Trump's goal to dismantle the "swamp." There's no way you do not realize this, although I doubt you will admit it.
Now with swamp creatures Biden and Merrick Garland, the DOJ leadership and the president are once again eye to eye ideologically. That's how Trump can claim Biden's DOJ is railroading him. But you already knew that.
So, in the end the DoJ does report to the President.