It is a directive which EU members must implement. The Netherlands is going to implement it in 2021. [1] I am unsure about the deadline for implementation.
You can try something like putting your router in bridge mode. For example Ziggo here allows that. KPN already allows free choice of "modem" (read: router). And a Fritz!box can be used as bridge if you use PPPoE client elsewhere. There's even PCI(e) DSL modems. A recent example [2].
[1] https://www.acm.nl/nl/publicaties/acm-consumenten-mogen-eige...
[2] https://www.draytek.co.uk/products/business/vigornic-132