That would be awesome to delete a column even if there is something inside.
User case: I have a column with hundreds of tasks that are completed. If I want to delete that column, I have to spend hours to remove or delete old completed tasks in order to do it. Which is painful and counterproductive. Thanks for considering that request!
Hi @Julien_Redelsperger just merging your post to gather all feedback on this topic! Hope this is ok, thanks for sharing your feedback!
I think that it would be easily achievable by replacing the delete column operation by a merge columns which would be the same as asking the user to which other column she wants to move all the tasks present on the unwanted column 
Hi folks!
Quick update to let you know we’re rolling out an update allowing you to delete Columns even when they contain tasks. We’re rolling this update gradually, as of today it is available to 20% of our customers, and we’re to roll it out to everyone within the next couple of days; so if you’re not seeing this option in your account just yet, don’t worry it will soon be available to you!
Let me know if you have any questions!
Hi Marie - if I have deleted a column, does this also delete the tasks in that column?! I tried the board view, and decided against it, then wanted to delete the headings so deleted the columns… now the tasks appear to have disappeared!