Well for most people it comes down to a question of how much money to spend.
In my opinion no system is future proof at all, it`s not like you have a crystal ball is it.
I mean for example you could buy a board one month and it can be super seeded by another just mere months down the line with a chip set that has a few more new innovations. And expansion options ect.
It boils down in my eyes to how you use a system, and what the main intended use for it is, above other things it can be used for.
Nothing is going to stand still, so the term future proof its self is a null concept even to state or mention.
What you are willing to compromise with depending on the amount of money you wish to part with to build a system.
Obviously you can replace a Cpu for a higher rated speed, or a slightly different architecture, to squeeze a bit more productive use to liven up a system.
But it`s a ploy in a sense to me, because when it comes around to a point it always involves for example a cpu socket with a different pin out on a new board forcing you in most cases to buck the cost of the Cpu and a motherboard to accept the chip.
When playing a game ect, everyone likes to have it running nice and smooth with all the nice graphical Eye candy on, but my takes is how well does the game play in respect to other things, longevity game play.
You can have the nicest looking game to the eye graphics wise. But be let down by a lot more aspects such as bad AI and more to do with a physical game and how its designed and by who for example.
Hardware will always be dogged, by the software side of things, for example you may have four core cpu, but if a program is not made by software to utilize the features, then where is the improvement ? There will always be a gap between physical hardware, and the software made to utilize it, as history shows.
When you buy a later model of hardware say a Graphics card, it often contains only a small number of tweaks. examples are faster memory or a more new chip design to enable lower power consumption by Die shrinking. Or such as the case with a Amd ATI 285 card support for the new direct x 12 feature, and true audio with CGN feature.
Even if you make hardware with new features, there is going to always be a lead time where, when it`s implemented from where for example software houses making games put it into effect and use the features available to them of the hardware. Most wont bother for example to implement the new features based on the the amount of hardware sold in numbers. And as a general rule most games made on a pc have a wider factor of hardware to support in types of graphics card.
Its a lot more easy to code or make a game for a console like a PS4 because you don`t have to worry about lesser hardware requirements.
This involves less time since it is propriety hardware, just one for all to make the game run at it`s optimum speed.
All the systems and hardware specs are the same, where as said with a pc you have to cover a more wider range of support for Graphics card brand and types, old standards and new ones implemented in new Gpu`s.
Here lies the problem in relation to PC games for example.
To get more life it`s a case of lowering the resolution of a game and the eye candy displayed.
In a sense to play a more newer game a few years down the line.
Like I said its all down to money, and what your willing to compromise with.
As the system ages, and hardware moves on.
Or you end up being a daft dog chasing it`s tale around and around trying to grab it., The dog is never going to get it`s tail its at the other end of it`s body. And a user who buys a system is the same in comparison to the people who invent and make the hardware. So how far do you want to go to convince yourself such a thing as the term future proof is a solid concept in your own mind.
Simply it isn`t. You never going to catch that tail just like a dog are you, no matter how much you think about catching it. Its always in front of the dog looking at it`s own tail, to try and catch it.
Just a quickie how many programs, or games in percent utilize or are programmed to use eight cores of a cpu, If it`s not it means the program and amount of data is slower for example if using four cores at the same clock speed vs eight cores.