What do we mean when we use the word modern? Deely's writing on The Impact of Semiotics on Philosophy referns a lot to modern philosophy to contrast it sharply with a much more up to date view that exposes mistakes that were at the core of modern philosophy. Whatever it is exactly, and whether it has ended, it is curious that a word that indexically points to whatever is most up to date has become iconic (symbolic) for a particular moment in the history of philosophy. Since the linked article uses Wittgenstein to delimit the end of the modern period, a quote from him is fitting:
If we take eternity to mean not infinite temporal duration but timelessness, then eternal life belongs to those who live in the present.
— Ludwig Wittgenstein
Our collective hangover from the 19th and 20th centuries is deeply connected to the problems of modernity. Perhaps it is an inevitable developmental crisis of emergent rationality, and probably it is even more deeply tied to particular cultural movements to completely supress the id. Whatever the origins and what terms you might use to explain it, the basic mistake is one of interpretation. As we have seen in exploring Semiotic Realism, there is a mistake common in the idealist tradition to project the ideal of a final interpretation that never occurs directly in the unfolding of the real, physically and in experience.
The positivism that resulted from the remarkable, if limited, success of the rational program of scientific discovery and resulting engineering successes led rational man to assume that this program would be ultimately successful and soon. Now that mechanical minds have been built and we have begun to intellectually explore what that means for: 1) Understanding cognition and how rational thought might emerge from it, 2) Showing just how much computational work is involved in simulating anything real be it physical systems or even more critically biological systems and intelligent organisms, and 3) Our conceptions of who we are and the role of objectivity and rationality in the structure of reality. One important early result is that all of it is a lot harder that the early enthusiasm might suggest, but that's a good thing for those of us who like the idea of an open future.