Fourth Wing (and its sequels) are a once-in-a-decade literary and sales phenomenon and honestly it would have been surprising if it had not been greenlit with a (relative) quickness. This is not necessarily the experience of most writers with works under option.
I saw it confirmed today that Amazon/MGM has committed to producing Rebecca Yarros “Fourth Wing” series for TV. The success of that series is transcendental. MLB is doing “Fourth Wing” theme nights. Romantasy has such broad appeal.