Muslims (Sunni Muslims) revere/respect all important Islamic figures unlike certain others. We don't worship them though. The only one that is worthy of worshipping is Allah (swt). That concept migth seem alien for certain elements in the region.
Banu Hashim and Banu Umayyah were/are very close relatives belonging to the same ancient tribe (Quraysh) and the people in question even shared the same great-great-grandfather.
en.wikipedia.org
The Umayyad dynasty was a great dynasty as well and the largest, wealthiest and most powerful Islamic dynasty in history and the largest empire/caliphate ever founded by any non-Western people outside of the short-lived Mongol Empire. Their legacy is felt from France/Al-Andalus/Western Africa to China/India in the east. From Al-Aqsa, Dome of the Rock, Umayyad Mosque in Damascus to Umayyad Mosque in Córdoba. Without the Umayyad's, Islam might have been a marginal religion.
But all this is irrelevant in the context of the Houthi terrorist cult and its illegal temporary occupation of Northern Yemen.