When I joined a big tech company the hardest part of ramping up was learning how to operate in that environment. There are a lot of implicit behaviours a "good" engineer is supposed to that you mostly have to figure out by yourself. Some of them are genuinely useful, but I think a lot are basically a kind of filter: https://twitter.com/danluu/status/1555077502803947520.
From what I've seen, the main skill for promotion in my company isn't engineering a well designed system, it's being visible and finding/creating the right projects.
I completely believe that someone could figure out how to behave like a higher level engineer and even succeed in their team, then get put in a different environment and completely flounder because they were mostly just copying behaviours that worked in their current environment, not learning fundamentals.
I'm also curious, vaguely what archetype was this Staff engineer: https://staffeng.com/guides/staff-archetypes.