Second, it's fine with me if some site wants to forgo my patronage, or provide "a deprecated experience", but not the government.
I certainly do expect my federal, state and local government to follow best practices and provide working websites that I can use without running JS.
I can't think of a single function of government that requires JS, thank God.
Best practices is a moving target. What made sense in 1999 doesn't make sense in 2019. The web simply requires JS, CSS, and HTML today. If you disable any one you aren't compatible.
There's no actual argument for why websites should spend significantly to support a tiny subset of users that intentionally break compatibility for ideological reasons. It is unfair to our other >99% of users who we'd have more time for.
The old arguments such as accessibility aren't correct any longer: accessibility devices specifically support JavaScript (text contrast, HTML organization/order, aria tags, video subtitles, etc remain highly important).
If you really insist on a JavaScript free world you are of course welcome to visit a government office in person, pick up, and mail back a paper form. The website is merely a convenience we offer to you.
Otherwise you'll need an IE 10 or newer browser, on an Operating System that supports TLS 1.1 (Windows Vista or newer), JavaScript, CSS, and HTML.
If you do web for a living, you should also know that fallbacks and graceful degradation and server-side rendering all come with a cost. Both monetarily and in terms of complexity.