This is essentially fraud. The makers of the software cheat to achieve the impression of improvement. WP sites use the software to improve their page experience ranking. But that is based on Core Web Vitals which cannot be cheated with this mechanism.
🚨 How "WP Optimize" is cheating PageSpeed and other testing tools 👇
When a site is loaded, the JavaScript files are loaded only when the user-agent/browser is not Lighthouse/GTmetrix/Headless Chrome/Pingdom.
No JS = high scores. But for real users, these JS files are loaded!