Here’s a list of the 551 permissions implicitly granted to every app that’s granted Shizuku/ADB access (including Shizuku itself):
Yes, many people can and do figure out how to install and use Shizuku, but hardly any of them understand the security implications. Let’s not make it a requirement to grant 551 permissions to apps like F-Droid and Obtainium in order to install any APK we want on certified Android devices, while currently it only takes one.