The culture of a startup is greatly determined by the founders. Most likely the DNA of the startup will be THAT striking attribute of the founders.
Zuckerberg was a hacker and that’s a core quality around which Facebook is being built.
Larry & Sergey were PhD CS majors from Stanford. That’s why it’s super hard to get into Google if you don’t have a CS degree (and a top ranker) from a major university. I think it subconsciously forms the culture of the company. And you can list many more examples.
Before you jump into a startup, it’s best to know the attitude of the founders. One striking quality that comes to mind when you say the founders name will most likely be the DNA of the company. If you’re not able to place a single prominent adjective against the founders names, the ride will be rougher.