> How would we know if we had reached this level of "individuality"?
> And has anybody reached it yet in human history?
A "we" that had reached it would, by definition, "know" it. Such a "we" has yet to come into being. There are good reasons for doubting that it ever will. As I've more than once argued, Marx's account of how the historical process will work to bring it into being is badly flawed.
A "we" that hadn't, might "know" what such a level would be without having itself developed it ("knowing", as Kant puts it, "how a shoe is made" being different from "knowing how to make a shoe").
The "we" represented in the pictures here
<http://www.withoutsanctuary.org/movie1.html>
has not developed the degree of developed "virtuosity" - the kind of "individuality" - required for "knowledge" of "socialism" in either of these senses. It's an example of a "we" made up of "those who think and feel wrongly".
It lacks even the developed capacity required mistakenly to imagine that a "socialist" society would be one where production was "engineered" by "planners" with the "individuality" exemplified by Frederick Winslow Taylor.
Ted