I've never even considered that a problem - my time between upgrades is so long that the last motherboard had DDR3, and the one before that DDR2. If you're a once a year upgrader I could see it, but given the slow progression of CPU performance as of the last half decade (AMD's rapid jump to parity not withstanding), I can't see a real reason why to upgrade that often.

With a motherboard bought with a Ryzen 1200 quad-core you could upgrade to a Ryzen 3900 12-core. In the same time frame you would have had two or three Intel sockets and chipsets.

And that's why I described my use case - as each chipset pretty much maps to an Intel generation, two or three different Intel generations doesn't provide a compelling reason to upgrade. Again, Ryzen is different, but that's largely because they've been fighting to gain parity with Intel.

It feels arbitrary.