Well, it may be that it goes like this: When you’re 30, where you’ve worked matters. Where you’ve worked depends (a lot) on where you went to school. Where you went to school depends (a lot) on what grades you got. What grades you got depends (somewhat) on how old you were when you took the tests.
Does where you worked depend that much on where you went to school, though?
Sorry if I am not convinced. In my country most schools are considered somewhat equal. Maybe in the US it is very different.
Oh yeah. Where you were/who you knew at 20/22 has huge, cascading effects on where you end up at 30, 35 years old. I won't get in to details here but a connection I made working at a coffee shop at 22 can be clearly traced to where I am now at 35. There is a lot of truth in "it's not what you know, it's who you know", particularly on the other side of 30.
Your story seems to indicate that it is not necessarily the school, though.