There has been some hopeful discussion that the silicone-covered keyswitches in the 2018 MacBook Pros could filter down to 2016 and 2017 models via repair.
There is some precedent for this; many customers with 2016 models have reported that Apple has replaced their keyboards with the 2017 variant. However, that does not seem to be the case this year, according to Joe Rossignol at MacRumors:
When asked if Apple Stores and Apple Authorized Service Providers will be permitted to replace second-generation keyboards on 2016 and 2017 MacBook Pro models with the new third-generation keyboards, if necessary, Apple said, no, the third-generation keyboards are exclusive to the 2018 MacBook Pro.
I had feared this would be the case. When a MacBook Pro’s keyboard is replaced, it’s actually the entire top case, with the keyboard and battery along for the ride. It is not an efficient repair, and one that was going to eventually lead to part compatibility issues between generations.
While I don’t know for sure, I have to guess that the screw boss locations needed for the revamped logic board, coupled with the higher capacity battery found in the new machines, dictated the change in repair strategy.
This leaves 2016 and 2017 customers potentially stranded with a design that is clearly less than ideal. However, many have reported that the failure rate on the 2017-style keyboard is much lower, so maybe this won’t be that big of a deal in the long run.