I don't understand the problem with it? If your needs are simple why would you drag in the JavaScript meme of the week?
I'm the tech lead for the NHS website (www.nhs.uk) and I oversee the team who are building this frontend library.
I'll be making sure we remove our jQuery dependency when I can. For now the team is simply aiming to get to an MVP that we can iterate on :-)
What does the backend stack consist of?
This is a very difficult question to answer comprehensively because our "website" does a lot more than just present information to people! Most of the content you can see on www.nhs.uk is Python/Django/Wagtail plus a whole heap of infrastructure. But there are aspects of our service written in C# or JS for example.