I think a way of addressing the problem with current switches might be to make the board with user adjustable anti-bounce. Have a small potentiometer (possibly screwdriver headed) hidden under the board where you can choose how much anti-bounce (would this come at the expense of response time?) you require. If the keys started to chatter, simply turn the dial up a little.
Another thought Matias might look at would be to adapt the design to make it capacitive. I was enquiring about Varmilo EC switches (before addressing the chatter on the Matias ones) and was advised they were like the Cherry designs, only with leafs that are made to work contactlessly. If Matias switches could be similarly reworked the feel that many of us enjoy could be retained but the bounce issue could be eliminated. Would it be difficult to re-engineer the switch in this manner? According to Keyboard Company of England:
What they did, which is clever, is took a Cherry MX and made it capacitive, simply re-designing the contact to 'not touch'. So it's not really that different, and a Cherry MX will work forever anyway.
Adding to the automotive metaphors relating to Matias already used on this thread, they say of the Matias switch:
...we like to keep it going because that is such a tactile switch and people really love them.
It is mechanical in the extreme, and like a Morris Minor, it has it's faults. But we love them.