@paperdigits is spot on for the reasons that the entire forum software defaults to having those minimum lengths. The idea is to really encourage more meaningful subjects as well as posts. (I already removed the minimum post length as requested by the RT team).
I happen to wholeheartedly agree with the reasons the discourse team chose to do this. However, we also happen to be very lucky in that our members are a bit more eloquent and trustworthy than most forums. 
Let’s ask the @staff in general if there’s any preference or strong feelings. I’m open to lowering it if desired - everyone is pretty good at keeping things focused already.