This is correct. I work in bot detections. There are baseline checks for various browser automation used as bot frameworks like Puppeteer or Playwright. Then there is basic analysis of server side and client side fingerprints; meaning, do the fingerprints you claim make sense. There are other heuristics too and I imagine Cloudflare is monitoring movements that point to automation. All of this happens after you click. I personally prefer this over Google’s captcha which frequently doesn’t recognize me as a human but is easily bypassed by bots.