We often have the idea of "solved problem" in science, but very few of them in software development (overgeneralizing a bit, any field of technology). This is probably because science is often about "what" (what is the fastest algorithm for matrix multiplication?), "whether" (does P = NP?), while technology is often about "how" (how to implement matrix multiplication efficiently?).
Once you solve a problem in science, you solve it for good. But in technology there can always be "better" ways to solve it, and things keep evolving.
We often have the idea of "solved problem" in science, but very few of them in software development (overgeneralizing a bit, any field of technology). This is probably because science is often about "what" (what is the fastest algorithm for matrix multiplication?), "whether" (does P = NP?), while technology is often about "how" (how to implement matrix multiplication efficiently?).
Once you solve a problem in science, you solve it for good. But in technology there can always be "better" ways to solve it, and things keep evolving.