"Google Play Protect" is a security feature included in Android devices (devices that support Google Mobile Service) that have Google services such as Maps and Gmail installed. A service that runs regularly in the background, rather than as a stand-alone app, detects security issues that may be included in the app.
According to Google's official blog, Google Play Protect works on all devices with the Google Play Store and protects more than 2 billion devices on the Android platform. In 2018, more than 50 billion apps were scanned per day, which means that simple calculations have confirmed 25 applications per day per device.
Google Play Protect restricts the system on the cloud (backend scanning engine) used for screening apps published on the Google Play Store, and the operation of apps that scan devices and determine that they are potentially harmful. Consists of two elements of the local system that alerts the user.
Because it is a function to prevent damage beforehand, it is difficult to verify what effect it actually had, but it is said that a warning message to the user was displayed about 100,000 times per day in 2018, so it works. That's for sure. It is said that even if the app has been malwared by the update after release, it is taking measures to stop publishing on the Google Play store when it is determined that it includes actions that cause privacy infringement and mislead users. It can be said that it has the effect of not spreading the damage. It is possible to turn off Google Play Protect, but it would be wise to keep it enabled.