I purchased a bag of 40 switches from AliExpress (store item) that are an exact match for the switches in MouseFan’s Apple Adjustable Keyboard. This was the first time that I have been able to examine one of these switches personally.
It is not clear until you’ve disassembled one yourself (be careful, as they’re fiddly to reassemble and easy to damage) — they are tactile by design. Apparently the 1994 Alps catalogue describes the switch thus: “Sharp ‘click’ feel with a positive feedback.” In practice, the switch is not completely silent, and can be heard to emit a faint click. However, having inspected the switch, it is clear that the intention was for a tactile switch.
Click leaf switches work by using a folded leaf spring that is caught and pulled forwards by the slider; when the slider travels far enough, it releases the leaf spring, which snaps back and strikes the inside of the shell. This impact is what produces the audible click.
The switches in the Apple Adjustable Keyboard have nothing for the leaf to hit. It’s well-known that Alps tactile switches do not have as much tactility as their clicky switches. The SKFS switch resolves this using an interesting approach: instead of stopping the leaf from being pulled forward, they placed the leaf further forwards. As the leaf snaps back, there is nothing for it to hit: there is empty space behind the leaf spring. The result is improved tactility without a click sound. The switch has a soft feel with distinct tactility.
Having identified this characteristic, it becomes clear that this is what is depicted on MouseFan’s Apple Adjustable Keyboard page: in the sixth photo, you can see the back of the tactile leaf below the jumper. This indicates that the Apple Adjustable Keyboard also used tactile switches, not clicky switches.
If Alps were to place a wall behind the tactile leaf, the result should be a click switch.