Pretty sure there was a hard landing by Skywest where tail icing was a contributing, if not the main, cause...

The 727 didn't have tail anti-ice either, but I've seen them completely iced up before...just like a CRJ tail. Just because there hasn't been an accident for tail stall (yet) doesn't mean it wouldn't be prudent to have tail anti-ice protection. The Beechjet has a known tail-stall issue related to icing (thing becomes a friggin' lawn dart!) and IIRC an inop tail heater is a no-go item.

I mean let's think about it, the airplane was designed by Canadians but it is absolutely horrid for errant EICAS messages when it gets cold-soaked and the flap fail issue has (in part) been attributed to slush/snow working its way into the system.