For the uninitiated, sideloading means installing apps from third-party sources instead of Google’s official app marketplace.
App makers have criticized this practice since it allows piracy.
Additionally, sideloaded apps don’t contribute to Play Store metrics like download counts and ratings.

There are also stability concerns improperly sideloaded apps can crash due to missing resources or equipment incompatibilities.
kill the dialog and the developers get notified, following which they can block all functionality.
A few apps have already deployed them, including popular games BeyBlade X and Diablo Immortal.
But for tinkerers, modders, and power users, it could be a major blow.