Copyright duration question: help requested

I'm astonished that Schumpeter's masterpiece, The Theory of Economic Development, first published in German in 1911, is not yet available in the public domain.

It is such a hugely important work. Everyone should read it. So why is it not available?

I checked and found that: "The provisions on copyrights in works created and published before 1978 are complicated, but, as a general rule, the copyright in those works will last 95 years. Anything first published in 1923 or earlier, though, is in the public domain" [Source].

But its translation into English only occurred in 1934.

So my question is: Is a translation deemed to be a SEPARATE piece of work, protected by additional copyright?

Could anyone clarify, if they know the answer?

Btw, the more I think about this issue, the more upset I get.

When knowledge is KEY to human progress, why are we copyrighting books for so many years? Would people not write books if copyright protection was reduced to, say, 10 years?

And particularly, if they produced the work at taxpayer expense (e.g as academics). Why do they have a right to block public access to that knowledge for 95 years?

I'm very fortunate that Anthem Press reverted all copyrights for Breaking Free of Nehru to me (won't go into details why, here). Imagine if the book was not available in the public domain for 95 years.