The matias quiet click arent really meant to be very silent. I think it alludes to the tactility of their clicky switch minus the click. Their quiet linears are dampened light linear switches, and sound less than most rubber domes.
Matias boards are just no-nonsense boards for typists. I dont like fiddling with my keyboard. No keycaps. No lubing. No swapping switches. I have done that. It is a distraction for me. I like typing on my matias board. When that dies I will get another one or maybe just use my old no-brand dome-with-slider keyboard (probably BTC) that I have used since 1994.