Sighted person here. I'm very interested in this question. Most developers I know are not considering accessibility as part of the intrinsic design of an app. Blind people are more keenly aware of this problem, unfortunately, because it affects them a little more directly. Accessibility to screen reading clients is considered a "good to have," nonessential, an optimization. And yet when you ask the same people if search engine optimization is considered a "good to have," many will laugh and say no, that it is a necessity, if for no other reason than their clients demand it.
Clients want sites that implement current SEO best practices. What sort of best practices are those? A Yoast SEO plugin, maybe. Developers often mention the URL structure of the site itself, say it's "clean." This might be appreciated by future admins of the site, but it's unrelated to the goal of making pages that can be scraped.
It surprises me developers and SEOs overlook the difficulty of scraping the web. Keyword density does very little to help a page that cannot easily be serialized to a database. It's true that machines have come a long way. Google sees text loaded into the DOM dynamically, for example. But its algorithms remain deeply skeptical of ( or maybe just confused by ) pages I've made that make a lot of hot changes to the DOM.
And why wouldn't it be? I ask myself how would I cope with a succession of before and after states, identify conflicts, and merge all those objects into a cached image. Badly, sure. At this point, summarizing what the page "says" is no longer a deterministic function of the static page. Perhaps machine learning algorithms of the future will more and more resemble riveting court dramas where various mappings are proposed, compared to various procedural precedents, and rejected until a verdict is reached.
I wasn't very good at SEO. I found web scrapers completely fascinating, I spent way more time reading white papers on Google Research and trying to build a homemade facsimile of Google. Come to think of it, I did very little actual work. But I took a lot of useful lessons that have served me well as a developer.
I realized, for example, how many great websites there are that are utterly inaccessible to the visually impaired. With very few exceptions, these sites inhabit this sort of "gray web," unobservable to the vast majority of the world's eyeballs. The difficulty of crawling the web isn't simply related to the difficulty of summarizing a rich, interactive, content experience. They are instances of the same problem. If I really wanted to know how my site's SEO stacks up against the competition, I would not hire an SEO to tell me, I would hire a blind person.