@quixoticgeek I haven't commuted by train in a bit, but this brings back some frustrations
The having to get their wallet and correct card ready problem already existed before contactless, with normal wallets and OV-chipkaarten.
On the station I most used, I had to get through three gate lines, two to get over the bridge, and then one more to get to the platform that was for some reason not connected to the bridge.
The first time I checked out during rush hour at one of the poles, it was as described so quickly that the screen didn't change, and the beeps were indistinguishable, but with poles, even more people can use the same one faster. This lead me to think I hadn't checked out, so I tap my card on the other pole (less in the walking way, so nobody used it) and checked in. Now I couldn't check back out, because both poles refused to do anything with a 5 minute timeout before I could tap my card there again.
The QR code reader faces down behind a transparent piece of plastic. Some ticket gates are outside, and get wet in the rain, now try to scan a paper ticket through the wet plastic, it wont work, and your ticket is soggy now, hopefully you brought something to dry the reader and are still able to scan your ticket before its wet again.