Enable Chrome's Reader View manually, when it isn't offered?
Technically, it is possible to request on-demand reader view (also known as "simplified view") on Chrome for Android.

Chrome uses DOM Distiller to determine if a page is worth to be simplified, then simplify and render it as a new page if requested.

There are a few ways to load a URL in reader view:


(Manual) from chrome://dom-distiller, a debug page that allows a user to input a URL and force load it in simplified mode.
(Possible idea for automation) a unique URL for every simplified page, which can be directly accessed from the address bar.

chrome-distiller://&lt;UUID&gt;_&lt;HASH&gt;/?url=&lt;URL&gt;


Where:


UUID: Universally unique identifier. By default, it uses UUIDv4 (random), but any UUID works, including nil UUID (00000000-0000-0000-0000-000000000000)
HASH: SHA-256 of URL
URL:  target URL (optionally, percent-encoded for safety).




Example URL for this page:

chrome-distiller://00000000-0000-0000-0000-000000000000_07036109224c60335e35e3b4c22dd02cf775f69d4430245c4c454aff570d6787/?url=https://android.stackexchange.com/questions/218970





Additional reading:


Ctrl blog - The many URI schemas used by the browsers’ “Reader Views”
Chromium.org Google Group - [Android] [Reader mode]Instant reader mode for new tab or WebView