At least in pop music, plenty of successful bands (maybe even the majority) don’t know music theory, they just know how to make music that sounds great (through natural talent and/or hard work).
There’s even a school of thought that music theory is actively bad for pop musicians, as it will tend to steer you down well-trodden lines and stifle innovation. For example, Paul McCartney supposedly avoiding learning any music theory when he was learning the piano, specifically to avoid losing his originality. He got the words for Golden Slumbers from an old piano piece belonging to his sister, but had to write an awesome new melody for it because he couldn’t read the music! (see https://www.the-paulmccartney-project.com/song/golden-slumbe...)
I think the analogy still works, though. To play in an orchestra you absolutely do need to be an expert sight-reader, and ideally have a good grounding in music theory. So working at Google or Facebook would be analogous to playing in an orchestra. They don’t want buskers, they want somebody who can read and understand a Messiaen score.
And maybe a small startup is more like a rock band -- you can get along perfectly well without any theory training. But if you want to grow into an orchestra (or in tech terms, more like 100 or 1000 orchestras) some theory training is essential.
Also, even in a small group, a mix of backgrounds can be beneficial -- look at the Beatles again, where George Martin’s classical training was a significant part of the overall mix (not to say a key part; Martin was the fifth Beatle at best).