Btw you can still buy an anonymous SIM card with cash in the Netherlands in pretty much any supermarket/kiosk/whatever. And if you just need Internet, I haven't had any eSIM provider try to verify my ID so far. Although those can't easily be paid in cash.
Are there services in the EU similar to Privacy.com? They along with US arm of Revolut lets you use disposable digital cards to buy things, but I don't know if such functionality is legal in the EU.
That will likely change too if it becomes the last bastion of anonymous SIM cards.