[mwpmaybe]

It's dependent on what you are hypothetically upgrading from. I'll be upgrading from a 2012 MacBook Pro w/ Retina, so I'm looking for:

* Thunderbolt 3 (from 1)

* USB 3.1 (from 3.0)

* NVMe (from SATA)

* LPDDR4 (from DDR3)

* An integrated GPU with sufficient power so as to eliminate the need for a dedicated GPU for my typical usage (from a 650M)

* More battery life / power efficiency

The specs for the MBPs that came out in late-2012 through mid-2015 weren't significant enough to justify an upgrade. It's not that I'm "desperate," and I can't speak for the GP, but this machine is starting to show its age (battery life, fan noise, etc.) and I really don't want to drop $2-3K for a new unit with mid-2015 specs.