My router was playing up, initially I couldn’t get my phone to connect, which I thought was my fault - since I started running grapheneOS but then other devices stop connecting and then those that were connected couldn’t access certain sites etc.
I still live at home, so my mum who isn’t technologically literate phoned the ISP, and attempted to fix it. Turns out it just needed a reset, as the last time it had been reset was 8 years ago.
What was a surprise was that the ISP guy told my mum how many devices were connected to the internet. She found that immensely creepy.
I doubt there’s anything I can do to reduce the trust burden with an ISP, beyond telling my mum to use a VPN. My threat model always had ISPs as a risk that had to be taken, however I am curious as to if there is anything at all that can be done! That’s also not immensely impractical?
Ah, see, I was talking about two separate devices, not an all in one: a modem and a router. But if OP needs an ONT for fiber, and the router is within the same device, I agree that they should just use the one provided by their ISP and add their own router.