It would be more practical in many places now to use leftover "hardline" phone plugs, especially because when they are disconnected from service they are sometimes quite literally disconnected and you have much fewer concerns about bleedover into neighbors.
Speeds won't be great for that sort of ethernet-over-phone wire, especially because most landlines used awful, cheeap wires, but in some cases it is faster than powerline adaptors.
Unfortunately all the companies that produce such equipment for "phone line adaptors" sell only to the phone companies and never directly to consumers.
So many houses today have vestigial phone wires that no one is using for anything.
Speeds won't be great for that sort of ethernet-over-phone wire, especially because most landlines used awful, cheeap wires, but in some cases it is faster than powerline adaptors.
Unfortunately all the companies that produce such equipment for "phone line adaptors" sell only to the phone companies and never directly to consumers.
So many houses today have vestigial phone wires that no one is using for anything.