I don't mind having a wattage limit on the slot. That's easy to factor into purchasing decisions. The much bigger issues are how custom each kind was, with very limited competition on individual modules and a big conflict of interest in wanting to sell you a new laptop.
A friend of mine was betrayed on this by MSI, where laptops with GTX 900 series GPUs were promised upgrades and then when the 1000 series came out they didn't offer any. I think they did make weak excuses about power use, but a 1060 would have fit within the power budget fine and been an enormous upgrade. A few people have even gotten 1060 modules to work with BIOS edits, so it wasn't some other incompatibility. It seems like they saw they couldn't offer a 1080 and threw out the entire project and promise, and then offered a mild discount on a brand new laptop, no other recourse.
A friend of mine was betrayed on this by MSI, where laptops with GTX 900 series GPUs were promised upgrades and then when the 1000 series came out they didn't offer any. I think they did make weak excuses about power use, but a 1060 would have fit within the power budget fine and been an enormous upgrade. A few people have even gotten 1060 modules to work with BIOS edits, so it wasn't some other incompatibility. It seems like they saw they couldn't offer a 1080 and threw out the entire project and promise, and then offered a mild discount on a brand new laptop, no other recourse.