It’s more concerning when you realize that most substation hardware is custom, built on demand for that requirement, not a generally stocked part. If a big transformer in a substation fails (or is destroyed), there may be one or two spares, if that. If a bunch of them are damaged at once from coordinated attacks, EMP, etc… you’re looking at years to rebuild that capacity.
There are so many things vulnerable to such easy attacks the only thing we can really rely on is the stupidity of most would-be wrongdoers and the ability of people to notice something hinky.
When I was in college, the campus lost a transformer for some reason. two or three of the dorms were without power for months (6 months?) and were running off of tractor-trailer sized generators. If you want to build a new (multi-megawatt) data center, and there’s no existing transformer? I hope you planned years in advance!
Also, I drive past that (peaker) generation plant and substation regularly. they replaced the chain link fence with one of those quick tilt-up cement walls. while the walls themselves are tall, the hill across the freeway from them is taller.