In theory, but I'm not sure that's true in practice. There are plenty of mundane, non-groundbreaking tasks that will likely be done by those electrical engineers and the more people, the more space, the more tasks are to be done. And not to mention more engineers does not equal better engineers. And the types to work on these sorts of projects are going to be the best engineers, not the "okay" ones.
The more engineers you can sample from (in absolute number), the better (in absolute goodness, whatever that is) the top, say, 500 of them are going to be.
That's assuming top-tier engineers are a fixed percent of graduates. That's not true and has never been.
Does 5x the number of math graduates increase the number of people with ability like Terrance Tao? Or even meaningfully increase the number of top tier mathematicians? It really doesn't. Same with any other science or art. There is a human factor involved.
This is not necessarily true. Hypothetical, if most breakthroughs are coming from PHDs and they aren't making any PHDs, then that pool is not necessarily larger.
You just said what I said. I didn't say that 100% of the graduates are stupid, but certainly not all high tier either. We aren't in extreme need of the average electrical engineer or the average software engineer. That's a fact. Look at unemployment rates.