All of the concerns are handled by robust existing infrastructure. That's the point. That ultimately the website backend doesn't matter, our intuitive logic and apprehensions about this stuff simply doesn't apply
Let's take an extreme example, pretend they use GoDaddy as their registrar and someone falls for a phishing email hijacking the domain. The Whitehouse not only could probably seize it back with a single phone call but also get the right people on the phone to stop the DNS record propagation at the root servers as well.
It's kinda like how the police keep their cars running when they're parked and nowhere around. They don't have to worry the same way you and I do about someone smashing the window and driving off, the infrastructural support for their vehicle is vastly different.
Or how the president doesn't have to worry about when to leave for somewhere to beat traffic because the police literally clears the road the president is currently traveling on of all vehicles like Moses parting the sea. It's a completely different kind of logic
...which is a bit like Russian Roulette.
The podcast ones for instance, they'll allow you to schedule the publishing of a new episode, then upload the episode to all the major platforms, format the images, titles and descriptions automatically for the different platforms, cross post to the social media accounts announcing the new episode, allow you to put in show notes for the blog, and embed a way to listen to the show on the site, all built in, for free, using an interface that is clean and well documented.
Of course I could do that myself but come on now, that simplifies my life so much.
I'm ok with my government saving money and not hiring six figure tech workers to custom roll effectively a press release website. Honestly, they could redirect it to a medium blog and save on the hosting fees as well. The real infrastructure is going to be at the departments, NASA, Smithsonian, CDC etc...