Motherboard has a nice explainer today: "The Clever Engineering Behind Intel's Chipocalypse"
https://motherboard.vice.com/en_us/article/qvw3k3/the-clever-engineering-behind-intels-chipocalypse
@schlink Notice that it's not «google» it's public research from university and a guy from google.
but tbh this birdsite thread may be the clearest not-too-technical explanation of the flaw that I've seen https://twitter.com/FioraAeterna/status/948684092333158400