Also, zooming and changing browser window size is, while only a keystroke away, isn’t something I want to do just to make a site that should be optimized for reading text more legible. It should just default to that way.
In short, I’m sorry this doesn’t fit your flow. That’s frustrating. But I think this is a better design. Matthew Butterick’s Practical Typography seems to support this view. [1] (MB is a lawyer, typographer, and Racket programmer for those not familiar with his work.)
[1]: https://practicaltypography.com/page-margins.html#on-the-web