alt Hacker Newsis like much of the discourse around the changes, overly sensationalized and borderline false.
The only change made that's relevant to sideloading-a-downloaded-APK as far I understand, is a 24hour delay in enabling the ability to do so, which is a wildly overblown non-issue.
It is less secure though, and they are doing it in the name of security. People are right to call that out as bullshit.
Availability is a key component of security, and this is a 24-hour DOS on apps not blessed by google.