Thread creators shouldn't be able to delete entire threads
Several threads that I participated in in the past couple weeks have disappeared, and based on the content of the threads, I'm guessing the creator of them regretted the content of the thread and buried it. This doesn't seem productive for the boards community.
Allowing people to delete individual posts is certainly fine, but somebody shouldn't be able to create a thread, see that they're getting disagreed with and downvoted, and just remove the entire thing. I'm not gonna pretend that it isn't frustrating for me personally to be denied "winning" an argument in this fashion, but of greater importance than my individual satisfaction, important posts from Rioters occasionally get removed as well.
The recent announcement that individuals of honor levels 0 and 1 wouldn't get reset with season 8 has sparked a bunch of posts about being stuck at honor level 0. Riot Tantram personally commented in two of these threads with relevant and important information about how recovering one's honor level actually works, which presented a source to cite for others responding to the threads popping up. However, presumably due to downvote embarrassment, both threads have since been deleted.
For a thread author to have the power to unilaterally bury the discussion that they began seems at odds with effective and consistent communication.