Double Debunking

Why did semiotics develop as a discipline that concentrates on the concept of sign, and that sees and interprets the world through this concept? Why was the idea of a science that systematically studies signs welcome in a certain epoch of humanity, and why does it seem so abstruse to most nowadays? Should it be given up, like something that belongs to a remote, vanished past? Or is there something, in semiotics, that still offers answers that no other discipline can provide?