That actually sounds kind of awesome. It's easy to get sick of the same Rails news over and over. Plus Ruby has such a vibrant and exciting world beyond Rails.
Calling a conference "Railsxxx" and then not doing any Rails sounds weird to me.
Why Railsberry? => it's still for Rails devs by Rails devs. And we love our name :D
In any case, you are doing great work and I am sure that Railsberry will be a success again!
That's actually a plan we came up with with Rails core team guys and hopefully Rails community can benefit A LOT from this open-minded approach!