I think the question is somewhat ill-expressed.
As far as I understand from the description, you're interpreting open source contribution in a very specific (albeit typical) way:
1. generically contributing to a well-known project to get recognition by the industry;
2. get hired in a certain project team through specific feature(s)
I generally discourage approach 1, for a couple of reasons.
The first is that a lot of people in the industry try this way (I did it, too), and this makes "newcomers management" onerous for projects.
The second is that commitment to newcomers is unrelated to the project size/fame. You'd think that large and established projects necessarily care about newcomers; there is no such connection. A notoriously committed community/project is for example GitLab; I won't mention another "very famous project" who couldn't care less, instead (to the point of labelling issues as "good first issue" and then ignoring them).
There are obviously project-external devs who gets their code approved, but based on what I've seen, they're people with experience in the field, and who work in a more targeted fashion (ie. approach 2).
I don't have experience with approach 2, however, if fits exactly the GSoC initiative, so you may either try to get in, or, in order to find a real-world answer to your question, research how many of the GSoC students are generally hired.
My opinion related to improving one's career by contributing to open source is to contribute to welcoming projects that you find interesting, and get known in the field. In other words, networking. I think start working on a famous/big project with career in mind has a very high chance of leading to frustration.
My direct answer to your question is "yes, I do know people who got a job with their involvement in open source", and it was about networking, not about working on a famous project.