I work in tech, at one of the big tech companies (the Rainforest one).
The dirty little secret of tech is that you don’t need the best engineers. You just need people that are “good enough”, and that bar varies wildly across all of tech. I’ve worked with senior engineers from Google that absolutely crumbled outside of building Python web apps, and recent grads in LCOL areas that are better in all areas.
Alongside this, many tier 1 services in big tech are propped up by mid-level engineers. Depending on the company and org, you’d be shocked at how little coding some software engineers actually do, because they’re attending WBR’s, building review decks, running all scrum ceremonies, even responsible for multimillion dollar team budgets. Again, many of these people aren’t particularly talented compared to your standard engineer.
You’re absolutely right, but I doubt any big tech company cares. They want to reduce human cost as much as possible, and if that means letting everyone that knows how shit works go, and hiring new grads to keep your systems alive, so be it.