After a long and deep analysis, I’ve come to the following conclusion:
Niantic delayed the release because of the several difficulties they encountered when trying to apply the occlusion technology smoothly (it is impressively difficult to handle).
All WU features were complete before the end of 2018, but since Niantic wants Wizards Unite to be the launchpad of their new technology and give the players the opportunity to feel a FULL and REAL immersion in the augmented reality, they delayed the release. So, don’t worry! They’re closer than you think
p.s. Keep an eye on Wizards Unite social media this coming week, big news are coming!