Very true, but the thing is, one doesn't need to know everything.
There is a saying 'A wise man doesn't know everything, but does know where to go to find what he needs'.
In our case, we start with the fount of all knowledge; Google. And work our way from there.
It was one of the problemsd with things like the five year apprenticeships of old. You spent five year learning things to a depth that was quite unnecessary in real life.
And then spent the rest of your life only using a small fraction of what you knew.
Academic knowledge is fine for academics. But the rest of us don't need it.
Particularly in today's hi tech age. And specialists are only good for the time it takes some machine or an algorithm to learn their job.
The ability to pick up as much of a skill you need quickly is more useful than complete in-depth knowledge.
But we do need a percentage of the population to really study things. Almost like a 'priesthood'.
I understand your point. However, what we do need is enough knowledge and understanding to give us context.
Anyone who is asked, "What is the atomic number of gold?" can look it up. Similarly, if they are asked the date when Shakespeare died, or who was prime minster when WW2 started, or what is the capital of Namibia. However, without context, these are mere factoids: pub quiz answers that mean nothing in themselves.
A person who does not have enough information to give them context is likely to make dangerous mistakes and to fail to see important connections between ideas. Very simply, they will not even know that there is something they need to look up. You will recall the famous "Known unknowns and unknown unknowns" speech. The unknown unknowns are the ones that get you every time.
I currently work in customer service dealing with queries and complaints for a tool and machinery retailer.
Every working day I speak to people who have bought 110V tools to run off domestic mains (which requires a 230V tool), or compressors that are inadequate for their air requirements, or pumps which they expect to "suck" water 10 metres up out of a well. People buy a compressor capable of 8 bar pressure without realising what they need is not pressure but volume.
These people have made mistakes, not because they didn't look up what the mains voltage is, or how to calculate air requirements, or what is the maximum distance you can draw a column of water, but because they lack sufficient understanding to give them a context: an understanding that would warn them that there is something important that they need to look up, or ask someone about, before they make their purchase.
This same principle applies across life, not just in the sphere of specialists and scientists, but in the every day fields of personal safety, home economics, disease control, the law. A person with no knowledge or understanding of a subject may believe whatever they are told if they are told it sufficiently confidently.