From the last time I delved into the news it sounded like third party devs could still get signing keys as long as they verify their identity.

I think alphabet is trying to kill ad avoidance tools. That’s my best guess on the economic motive here. If blocking ads is against their ToS or terms of use, and you can’t publish ad bypassing tools, suddenly Google can guarantee their walled garden has more ads than piracy websites or porn sites…