Apparently, they were negotiating who gets how large a cut from Spidey flicks. Disney wanted a 50/50 split. Sony left the table and didn't even counter.
Meanwhile, Holland and Watts are under contract for two more pics. Too soon to tell if they are retained or Sony goes for another reboot.
Edit: Of course, this may just be the opening salvo in negotiations. Maybe the two parties salvage it in time for a new release date.