I think we should remember that the vast majority of computer developers and engineers will not, and probably never, work on stuff that requires deep understanding of things like data structures and algorithms, even those with advanced degrees. Most are just, how to put this, IT janitors.
To use your mechanic and mechanical engineer analogy: They're not even mechanics, they simply change the oil and light bulbs from time to time, along with cleaning the interior.
Not saying that it's not useful - you'd get a much better understanding of things...but this obsession with learning everything under the sun just to be "ready" for the job is overkill
I guess it depends what you want to work on and what your career goals are. I think my mechanic vs mechanical engineer example is actually a pretty good analogy of actual conditions. You have (many) people learning how to use tools and fix known problems (like mechanics, or e.g. CRUD developers) versus the others that actually need to solve problems with unknown solutions or optimize existing systems (the engineers). Maybe also with known solutions, but with a far deeper theoretical knowledge as a base for doing that.
Yes, the majority of work is on solved problems and we need far more mechanics than engineers. But it's not such a clear cut and a lot of actual software engineers work on solved problems most of their time and only spend a small amount of time on the engineering part (which is probably similar to other engineering disciplines). But when you spend the small amount of time on engineering work these basics are important and I realized multiple times that I could make better decisions because of it. And I'm kind of certain that's the case for most engineers with an academic background or self-taught basics though they might not even realize it.
From this perspective, which people/roles would you consider to be the software engineering equivalent of a mechanic? How about the equivalent a mechanical engineer?
To use your mechanic and mechanical engineer analogy: They're not even mechanics, they simply change the oil and light bulbs from time to time, along with cleaning the interior.
Not saying that it's not useful - you'd get a much better understanding of things...but this obsession with learning everything under the sun just to be "ready" for the job is overkill