Current state: Approved and merged
Discussion thread: here [Change the link from the KIP proposal email archive to your own email thread]
Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).
Topic deletion is still disabled by default in Apache Kafka. This means that with default configuration users need to figure out the configuration and modify it before they can delete topics. Since Kafka is typically first encountered in a development environment where users both want to experiment (which includes deleting failed experiments) and don't want to learn about new configurations, the current experience is suboptimal.
Topic deletion feature has been stable for about 2 years now. I think it's time to change the default.
# Switch to enable topic deletion or not, default value is false