There is actually some drama between Wiz and Orca, a company founded one year before Wiz. Orca alleged Wiz copied them, and Orca does operate in the same space. But a lot of hundred billion dollar companies are built on moats, integration and switching costs.
Yeah but Google is a trillion dollar company. Why do they need to spend $32billion on a company whose only value add seems to be they are good at finding exploits? You could hire every cyber security researcher in the country for $32billion.
It is a difficult question to answer. For example, why did Google acquire YouTube in the early 2010s? A platform technically and engineering wise similar to YouTube would have been very easy to replicate. IMO the best explanation goes back all the way to the days of Standard Oil/Carnegie Steel company - and quite possibly even the East India Company. There's an enormous benefit to consolidate various businesses under you and create a monopoly. Today in tech, monopolies are far from being as straightforward as being the dominant producer of a commodity like oil or steel. But there's undoubtedly some similar mechanisms involved. Synergy is one way to put it, but I think it's too restrictive.
I think the other part of the equation missing is if Google did create their own Wiz, Wiz would still be on the market, and it'd be a bitter fight which they could very well lose.
Google did in fact have a product that was technically similar and in fact superior to YouTube. Remember Google Video? It was better and people hated it.