MXM GPUs are going to be produced for long time to come. CLEVO, Aetina.... you name them. There are plenty manufacturers.
Even if the rumours about GTX MXM going away are true (which I doubt they are), I feel like an AsRock/PNY union on the Quadro side of things wold make for amazing compact workstations. If you consider the price of the following small workstation PC from Boxx (5.8L, well done srsly):
CPU: Intel i7-7700K
RAM: 32 GB DDR4-2400
GPU: Quadro K620 (165 USD Kepler card)
Storage: 512 GB SSD
Cost: 3773 USD
Looking at a higher end build, you can see Origin PC's Chronos S in the SIlverstonw ML08 (12.2L)
CPU: Intel i7-8700 (non-K)
RAM: 32 GB DDR4-3000
GPU: Quadro P5000
Storage: 512 GB SST
Cost: 3951 USD
Now obviously the Boxx is a massive ripoff and I have no idea how they get away with charging that for a 165 USD GPU vs a 2000+ USD GPU but whatever. Point being were you to build the same system on Micro STX you'd get something like the following:
https://pcpartpicker.com/list/ysXtm8
Assuming the Micro STX board in its bare form costs as much as the Z370 Fatal1ty, you get the same i7-8700 as the Origin, the same P5000 GPU (MXM Quadros tend to cost approximately the same as standard PCIe models), similar RAM (I chose a kit with approximately the same price as a G.Skill DDR4-2400 32GB SODIMM kit), and a 512GB Samsung Evo (I bet the Origin is shipping with a second tier M.2, not a Samsung). All of this for 700 USD less than the Origin, fits in one fifth the volume and has a markedly nicer case.