Our experience in April: We were unable to use our Schwab ATM card, which is chipped and has PIN, to buy tickets from the NL machines. We were later told that the NL ticket machines use the Maestro system, which Schwab is not on (it has Interlink, PLUS and Moneylink logos). The card did work for machines for French train tickets and for the Vlissingen Ferry.
As an aside, someone was there to advise me to get the "error message" printout (silly me, I was thinking of that as something to show to someone to view the computer problem). This was at Middleburg and we were going to Leiden, with no ticket agents in the station. This happened to be the only time we were ever asked for tickets on a Dutch train, fortunately we had the statement.