What you would like to have is not paying your ISP for the landline anymore right?
This is easily done by buying a SIP phone (used Yealink T30 start at 15€) and register a virtual number at a SIP provider local to you (e.g. https://sip.us/ starting at 1€/month). Just connect your phone to your regular network, they will give you a set of parameters to configure into your phone and it will behave like a regular landline after that.


Because other countries handle that differently than the Netherlands?
e.g. In Austria a not insignificant part of people exclusively do transactions in cash (think of that what you will). There even was a push to anchor cash payment is the constitution, so removing 100/200€ notes is not even on the table