One of the two options has to be chosen for the no JS, no query param / no login default - there is no entitlement and absurdity in that expectation. Using the max-width: none or similar as the default option has the benefit of allowing the user's browser keep the ability to monotonely scale the text density along with size using zoom as the displayed area would be nearly constant. It's rather arrogant & condescending to choose for a user a width that overrides what control they have with their window's dimensions, screen size, viewing distance & vision capability.

Ideally, CSS and not JS would be used to set the size of column text. But, that is not what Wikipedia is doing by default. Observe the behavior of the table on this page with & without JS: https://en.wikipedia.org/wiki/Binary_relation that occurs on not just that page, but all of the Binary relation pages. Note the dangling "in" at the top without JS with limited CSS styles on the table, but with JS the table becomes collapsed by default & the page text does not jump. The other JS only functionality that extends the page width that does not cause the page text to jump when the table is opened is the previously mentioned fullscreen "Toggle limited content width" button in the bottom right. Also, since I cannot edit the original comment here is the previous CSS condensed:

  .mw-page-container,.mw-content-container{max-width:none!important;}