How likely is that this will happen, unchallenged?

I've honestly just been hoping it never happens, because I don't actually have a plan to deal with it if it does...

I read this from Fdroid (https://f-droid.org/en/2025/09/29/google-developer-registration-decree.html) and I also looked at the Google announcement here (https://android-developers.googleblog.com/2025/08/elevating-android-security.html?m=1)

Things are still murky to me. Google said the following:

To be clear, developers will have the same freedom to distribute their apps directly to users through sideloading or to use any app store they prefer. We believe this is how an open system should work—by preserving choice while enhancing security for everyone. Android continues to show that with the right design and security principles, open and secure can go hand in hand. For more details on the specific requirements, visit our website. We'll share more information in the coming months.

Is the problem then that developers have to register? I see the downsides to this, but does it actually block side loading and using F-droid?