They do have to allow own modems as well as routers.
Article 5 of the EU Net Neutrality Regulation states that “end-users should be free to choose between various types of terminal equipment […]. Providers of internet access services should not impose restrictions on the use of terminal equipment connecting to the network […].” [1]
However, currently only 5 member states fully comply with this (Germany, the Netherlands, Belgium, Finland and Lithuania). [2]
E.g. NL ISPs provide all necessary parameters for PPPoE and SIP (telephony). [3]
I don't think that is true for modems, there is an "exception" for indirectly connected terminal equipments.
Interestingly satellite earth station is explicitly mentioned, so maybe we can use our own Starlink dish, but not out own modem... (law is weird)
‘terminal equipment’ means:
(a) equipment directly or indirectly connected to the interface of a public telecommunications network to send, process or receive information; in either case (direct or indirect), the connection may be made by wire, optical fibre or electromagnetically; a connection is indirect if equipment is placed between the terminal and the interface of the network;
I’m not a lawyer, so perhaps I’m missing something, but I don’t see any exception in your quote or link. Your quote literally says ”equipment directly or indirectly connected” (emphasis mine).
The Netherlands regulator interprets this by saying that “the network connection point must be passive” and “all (radio) devices that are located at the premises of the end user and that are connected to the network connection point are end devices”. [1]
> a connection is indirect if equipment is placed between the terminal and the interface of the network
If I check the official version in my native language, that (translated back to English by me) explicitly says:
> in the case of indirect connection there is an additional equipment/device between the terminal equipment and the interface of the network
If we assume that the the interface of the network is the optical or copper cable and the terminal equipment is your router, then (at least to my understanding) this additional equipment could be the modem of the service provider. The EU law doesn't speak about active or passive status of these equipments.
Maybe the Dutch law is stricter?
If you google translate the official French version to English via Google Translate, you got:
> a connection is indirect if a device is interposed between the terminal equipment and the interface of the public network
From German:
> in the case of an indirect connection, a device is connected between the terminal equipment and the interface of the public network
From Dutch:
> a connection is indirect when a device is placed between the terminal equipment and the network interface
Article 5 of the EU Net Neutrality Regulation states that “end-users should be free to choose between various types of terminal equipment […]. Providers of internet access services should not impose restrictions on the use of terminal equipment connecting to the network […].” [1]
However, currently only 5 member states fully comply with this (Germany, the Netherlands, Belgium, Finland and Lithuania). [2]
E.g. NL ISPs provide all necessary parameters for PPPoE and SIP (telephony). [3]
[1] https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv:...
[2] https://fsfe.org/activities/routers/routers.en.html
[3] https://www.kpn.com/w3/file?uuid=cd5f3398-4bad-4cdc-ac18-4f6... (DSL) https://www.kpn.com/w3/file?uuid=563993a1-e48a-485a-90a8-738... (FttH AON/PON) https://www.kpn.com/w3/file?uuid=b9774a1d-f1cb-4c17-8972-251... (SIP)