It's not impossible but writing the Puppeteer or Selenium incantations needed to scrape these sites (whose elements change fairly regularly) is a lot more work

It's not impossible but writing the Puppeteer or Selenium incantations needed to scrape these sites (whose elements change fairly regularly) is a lot more work than "implement this API and get tokens via OAuth standard grant flow" And that's before you get to the Cloudflare final boss