OK, I'll be that guy; the last overflow ripped away the last spillway like it was made of tissue paper; what's different about this one?

Sounds like someone didn't do their homework the first time.

https://www.mercurynews.com/2018/08/13/oroville-dam-see-before-and-after-video-of-construction-progress/

Also in January, an independent team of experts who reviewed the spillway failure concluded in a report that Department of Water Resources officials were “overconfident and complacent” and gave “inadequate priority for dam safety” for decades at Oroville.

They noted that main concrete spillway at the 770-foot tall dam north of Sacramento, in Butte County, was built in the late 1960s on poor quality rock. The spillway, only seven inches thick in some areas and not adequately anchored, cracked in multiple places in the following years, allowing water to flow underneath. On Feb. 7, 2017, water from powerful winter storms rushed under the massive spillway, which forced up its giant slabs and ripped a huge hole in the structure causing one of the most serious dam emergencies in California history.

Well--I hope they did their figures and figuring this time...