iirc (it's been over a decade), the Oyster card is a plastic card with an NFC in it. Montreal's Opus card does the exact same thing (and is probably modelled off of it and similar implementations in other cities). This article is describing the disposable, single-use ones.

If you don't want to use disposable ones, the same kiosk that dispenses the temporary cards will allow you to buy a permanent one which you can load with fares as normal.