The very idea of going around in circles in a hold at 150 knotsis pretty ridiculous, particularly when it goes on so long thatyou end up diverting to an alternate. Makes you wish you'd takenthe bus. Nonetheless, the feds really do want to minimize airborneholding and they use something called Flow Control to do it.
This is a companion discussion topic for the original entry at https://www.avweb.com/flight-safety/holding-improves-efficiency-yup-heres-the-logic