That's an interesting bit of detail. As you intended, it does not lessen the impact of the statement: "conditions never witnessed by us or our prehistoric relatives". It confirms it, with some additional context.

To me, it seems to make it even more significant. Because as you point out, Homo evolved under ice age conditions over millions of years. Well, here we are about to be thrust into uncharted territory, in an extremely short period of time. With very fragile global interdependencies, an overpopulated planet, and billions of people exposed to the consequences.