Agreed. Technology changes so fast, that something (coding, programming, method or reading data, drivers, hardware) could change and render your rig that you expected to last 10 years useless way before you expect.
Think about it this way. In the 70's in America we had big heavy cars people modified with 500+ horsepower to be fast. Then in the 80's these little Japanese cars (300zx, 240z, rx7) came along you only needed 300 horsepower to be faster than the big old cars from the 70s.
What I'm trying to say is that this isn't going to be a 10 year rig. That if DDR4 RAM comes out and you need it to run future games well? Then you have to buy a motherboard that supports it, a new CPU, maybe a new GPU setup if they can't communicate with the new motherboard. You never know. It just plain isn't worth it unless you have money to waste. If you do have money to waste, there are much more fun things to spend it on than a computer that will perform the same as one $3000 less expensive.