I’ve never been sure just how many keyboards on the 2016/2017 MBP had a real issue. The keyboard was redesigned at some point, and many actual users report no issue.
Then there are a few who complain about the keyboards being rendered useless with a “speck of dust.” Always that same wording, over and over... a speck of dust.
I don’t doubt for a second there are some number of keyboards out there that have/had a real issue. But given how this complaint has been harped on and amplified by those who hate the latest model due to ports/thinness/cost/touch bar/etc., I do wonder about the true frequency of actual problems.
It can’t be every unit, since there are plenty of reports that a new keyboard solved the problem, and there are millions who have never had the issue.
I can only speak from my experience - 3x replacement keyboards on my 2016 before I sold it. The 2nd and 3rd replacement were the supposedly “upgraded” 2017 keyboard, and they failed just as fast as the 2016.