Taking the article at face value, they'll have to register with google and have their apps be signed. Presumably this is subject to less review than the play store (eg. you don't have to justify your permissions list or whatever[1]), but there's no guarantees that developers will bother with the hassle. A lot of developers are willing to put some release up on github, but not dox themselves to google.

[1] https://www.hackerneue.com/item?id=41895718