Ret paladin is the worst spec in M+. They lack utility, they are super squishy, and dps output is low unless the tank builds a route around them.
They also seem to be a spec that many people want to play. Why deny people fun? Other 3-role classes have very viable specs for all 3 rolls (druids and monks come straight to mind). Why do ret paladins have worse damage and less utility? Warriors do way more damage, WW monks and rogues do much more damage and bring a lot of utility. Survival hunters have soothe and hero. Enhancement shaman have hero.
Rets have … uh … off-healing … oh wait no those other classes mostly do too … hrm … blessing of sacrifice? Oh wait no just bring a prot or a holy paladin instead. hrm.