There are lots of good reasons distribution companies don't like cables in some situations (especially rural). Connecting new customers and network alterations is much more expensive, changing to a higher voltage is not possible, upgrading capacity requires a whole new cable which is more expensive than replacing the conductors, cables only last about 30-50 years. Finding and fixing a cable fault usually takes much longer than overhead (although there are probably less of them per mile). Without wild fires, I seriously doubt cables are more economic in rural areas.
so then we rely on linux solutions instead? I've seen lots of control systems running linux and windows, personally I'd rather keep a mix of the two. Something about eggs and baskets.
They aren't 'on the internet'. They are connected via several layers of networks with firewalls etc in between to a system which has direct access to the internet. There often is no practical way around this - data from these networks needs to be shared with business users, other companies, regulators and so on. Data diodes can be applicable in some situations, but I've never worked with a company that uses one. I don't know the details of this situation, but demanding that it be impossible to compromise infrastructure networks is ridiculous. If you throw enough money and resources at it, no network is secure.
isn't this just a keepalive on the socket? no content actually being requested? If so I don't really see the problem. I had to write a reverse proxy the other day in nodejs to handle an unusual set of requirements that couldn't be satisfied by nginx\HAProxy and I did exactly the same thing - use an httpagent to keep connections alive to clients for a period of time (I think I chose 10 minutes or thereabouts) - without it sequential requests are about 10x slower due to SSL key calc overhead.
diesel might be a bit more efficient, but produces more nitrogen dioxide (and other oxides) which are harmful to humans and the environment, which is why they are being banned in some parts of europe.
especially when many of the devices have to be returned to manufacturer for the update... including a whole bunch of RTUs that run electrical transmission/distribution systems.
Obviously there is going to be an increased amount of solar and wind coming online in the near future, and I don't think that anyone running a power system network at the distribution or transmission level is going to dispute that. However there definitely is uncertainty about how much, and there is even more uncertainty about what our loads are going to look like with large amounts of EVs coming online and potential battery deployments. These things could have a big impact on the size and timing of grid peaks and inertia which can require big investments to manage appropriately. And as with any big investment, you want to make it at the right time, and you want to be sure that you are going to make a return on that investment.