“The gospel has been preached to ALL languages? There are no unreached people-groups? I don’t think so.”
http://www.joshuaproject.net/assets/handouts/bible-translation-status.pdf
There’s still many languages needing translation. It is a very difficult thing to accomplish. Many languages only have a gospel or portions translated. What about languages with very limited vocabularies. What about tribal languages where there is no written system developed.
Preaching is HEARING, not necessarily written.