Quantumbadger already put out his update. Summary is that he’s exempt from the new costs but we’re losing distribution channels which need source (ie fdroid repo) so he doesn’t publish his keys.
https://old.reddit.com/r/RedReader/comments/145du4j/update_4_redreader_granted_noncommercial/
I think the real answer has to be that he gave them real numbers he expected them to pay. They all said wtf no but he promised similar numbers to his investors from the official channels.
People who are doing better then him (profit wise) at his own game bailed when asked for things he promised to deliver.