Or, use techniques such as those in the article, such as random keypresses played during the actual ones.
Or possibly the exact opposite of that, I can't tell if it's a one-to-one mapping on mobile: https://www2.b3ta.com/buffyswear/
(Also, I'm feeling my age now, given how many years have elapsed since that kind of thing passed for internet culture…)
I’m sure it depends on the application to some extent. I can type my pin in without looking at all, so I can cover it up while doing it. If I had to hunt and peck, it’d easier for an onlooker to observe my slower motions I think.
But if I used the same machine often enough to produce wear specific to me, this randomization would be really useful.
Otherwise, you leave behind grease where your fingers touched
Yes, that's also obscurity, but obscurity is actually good - it only got a (deservedly) bad reputation from when it gets used as a substitute (but I fail to see how using a nonstandard keyboard layout would even count as obscurity in the context of an audio attack, as the clear text reference would surely go through the same layout?)
I'm sure customer frustration was huge.
[0] Okay... deep breath
Konami is a pachinko manufacturer with a side hustle making rhythm games for Japanese arcades. They have an online service that all their games connect to called e-Amusement. You can log into it using an e-Amusement Pass card, and your card is locked to a PIN number you have to set up when you first use it. Cabinets with touchscreens give you a touch keypad, except all the digits are shuffled around, which is a total pain in the ass and you have to do this for every credit.