Earlier quoted context omitted.
But that is the point. CSS arrived, and people started saying you "just need to distinguish beteen the semantics of" a table "and the layout effect". Back then, the chant of the day was, "blood for the blood god, tabular data for the god, layout for the CSS god". And then it spiraled into general "separation of content and presentation" nonsense that, like in any good cult, people believed with their whole hearts, pr…
Is accessibility for the visually impaired a cult? How could Google even work if content could not be seperated from its visual presention?
Approximately. Like it did and does.
The simplest way is to just strip the markup (or, for purposes of indexing, just ignore any token that resembles a HTML tag). That'll easily get you 90% there. You'll lose important information that's tied to form, but that's a consequence of operating in plaintext land. If doing this to build an index of the web, you'll have problem with scoundrels stuffing irrelevant text made invisible to humans by markup/CSS/JS, but that's exactly the problem Google used to have for a long time, and the essence of what SEO is :).