Not GP, but this reminds me of how modern GPON (including XGS-, 50G-) works in some areas, like NBN (Australia), NTT FLETS (Japan) and Openreach (UK) where the fiber runs, on what is essentially, a PPPoE or IPoE pipe that tunnels the connection from the customer to the real ISP the user subscribed. Switzerland (basing at least on Init7 docs) has somehow decided on fiber-optic being a real dumb pipe, which is really nice but I imagine that it is costly.