I don't know... the first Core i7 processors came out in 2008, and still perform well today.
If you got a high end Haswell chip now, it just might still perform adequately 10 years from now.
The problem usually isn't the CPU itself. In 10 years most peripherals might be USB-C and only legacy stuff ships with USB-A. dGPUs might be running on a x32 slot that's incompatible with old motherboards.
It's always a crapshoot where you'll land on those transitions. A Nehalem or SB computer will probably end up have a very long supported life. You could also get not so lucky with the timing. 10 years ago I was running a Barton 2500 on an NF7 that was only a year or two old at that point, and already it was close to obsolete. Even 4 years after I bought it wasn't worth upgrading to play newer games; finding DDR was getting harder, AGP cards were limited to a few ATI models, most new drives were SATA which the MB didn't have, etc.
An upgrade to C2D cured a lot of platform problems, and that computer wasn't even that old.