I see what you said in second sentence that state hard drive won't getting slower each years. My hard drive are getting slower, that I called degradation or lossing performance, then how do I get it back to normal speed?
You realize that's a data/software issue correct? Over time files get fragmented, causing longer seek times, causing slower performance. Nothing 2-3 Defrag cycles using <insert favorite program here> can't cure.
Moving hardware (literally, parts that move - platter HDDs, fans, cooling pumps) degrade with time; static hardware (parts that don't move - PCI slots, USB ports, ethernet ports) do not - when they fail, they simply fail. Incidentally, this is why HDDs most often have predictable symptoms that they are failing and SSDs just stop working with no warning.
If you have a USB port that's not working, it's the port. If you have one that slow, it's the component connected to it.