What an asinine position is taken by that publication. Swapping cables? For advanced new ones? Seriously? Such bullshit.
The real reason that transmission lines aren't upgraded in place is that there's often insufficient transmission capacity to reroute the power the old lines carry, and that when you deploy higher voltage transmission lines (the whole point) you need different tower designs, which means an expensive, time-consuming process.
OTOH here in CA we have an infrastructure, courtesy of PG&E, that drops power lines every time there's an even moderate high wind. Hence they announce black-outs for what seems no reason whatsoever, rendering this a power grid less reliable than Honduras or something. Lack of any investment for many years. I'll never forget being on Maui in the early 2000s for one of those company corporate "President Club" appreciation events, in a nice enough place right next to the Ritz Carlton. One evening I decided to walk over to the Ritz to change scenes and treat myself, and PG&E had rented the entire place for a week. Capital allocation clearly isn't the strength of de-facto energy monopolies - neglect investment in your core business infrastructure while partying like it's 1999, sure, that works... :-D They were pounding down the Opus One, too.