Call the Routing Police
blog.apnic.net
blog.apnic.net
Who do you think runs connectivity for your average electrical grid outside of the power cables themselves?
There are superposition modems but those assume that the lines themselves aren't damaged so there usually is a whole SCADA system on either a private cellular network or through fiber or copper (depending on age) owned by the telcos.
FWIW during the massive blackout in the early 00's in North America and Canada the telco system held up remarkably well (until the fuel ran out in some places).
The grid run their own lines. Underground power cables are always accompanied by a pilot cable, which used to be 2x current loops plus a bunch of twisted pairs, now fiber optic. Underground power cables are almost always run in pairs (pairs of 3 phases) so between every significant substation there's always at least 2 dedicated communication lines.
You have said 'owned by the telcos' and this is very much not my experience. The grid comms network is owned and maintained by the grid.
But even the largest grid infra companies here rely on the telcos for their private comms, for instance:
https://nieuws.eneco.nl/stedin-en-liander-bundelen-krachten-...
Note the mention of "KPN" for this private mobile network that is nominally owned by the energy company grid operators but in fact is operated by KPN (the largest Dutch Telco) and uses their infra.
Which country are you in?
You should read that article again. It doesn't say what you've said it says.
Creation and operational management will be supported by Telco and ICT service provider KPN.
I's secondarily like to point out that 'supported by' can mean many things, including merely having the telco as a depot for replacement equipment and repair services, etc.
More often than not long-haul fiber within a single metro area is owned by the electrical providers, and the telcos lease strands from them. Telcos will lease fiber from power companies but rarely the other way around.
The intercity stuff often belongs to power companies too, if it's within their service footprint. The Bonneville Power Administration owns most of the long-haul fiber in Washington, Oregon, and western Idaho.