They built the core CSPM module themselves. And, yes, their customers really do exist and really do love the product. What they particularly liked was the alert fidelity - most other cloud security vendors back when Wiz started required a host agent to provide a similar level of assurance a given alert was real, whereas Wiz would do offline volume scanning.

Just because you aren’t the target market for something doesn’t mean it isn’t real or valuable.

Source: used to compete against them. I no longer have any dog in this fight.