So unless you work in a medical clean room it largely doesn’t matter how clean you keep your laptop. Two top cases later for me and I now use a keyboard cover. No problems since.
https://www.amazon.com/gp/product/B019O1RH4W/
They are thin enough to allow you to close the lid of your laptop while traveling, and stop and direct contact from the oily keys to the screen.
I have to assume this implies a redesigned keyboard is coming, though. This is going to be expensive for Apple and it would be insane to stick with a design that they are tacitly admitting here is faulty.
The 2017 keyboards feel and sound better, but are no more reliable. I've owned two 2017 MBPs and both keyboards have had issues.
I have the new MacBook Pro and I prefer its keyboard over old style, but I swear the first time I used the down arrow about a week after purchasing it was slightly jammed with something. Still functions and doesn’t repeat characters, but infuriating.
It sucks to know that after 4 years this repair program will end and I’m stuck unjamming it myself by following this article: https://support.apple.com/en-us/ht205662