Casey Johnston, writing about the newest MacBook Pro, which as a set of silicone membranes designed to keep dust and debris from killing the keyboard:
Every time I described the 2017 MacBook Pro I sold because I couldn’t stand its non-functional keyboard and asked an Apple store employee if the new one would screw me over the same way, each assured me that Apple had changed the keyboards so that that would never happen again. I described my issues with “dust” to one shop associate at the Apple Store at the World Trade Center and asked if the new computers were any better. “Yeah, yeah, they fixed that problem… it was a BIG problem,” she told me. “So it doesn’t happen at all?” I asked. “No, it shouldn’t happen,” she said. Maybe the bad days were finally over.
But checking around online, it appears the new keyboards have the same old issues. They may be delayed, but they happen nonetheless. The MacRumors forum has a long thread about the the “gen 3 butterfly keyboard” where users have been sharing their experiences since Apple updated the design. “How is everyone lse’s keyboard doing? I rplaced th first one because ‘E’ and ‘O’ gave double output. The replacment ither eats “E”, “O”, “I” and “T”, or doubles them,” wrote one poster. “I didn’t correct the typos above on purpose.”
My 2018 machine’s space bar got weird for a little while but has since cleared up. I am nervous, however, that this issue isn’t really gone.