SMN is absolutely the #1 choice for supports that want to dps but have never done it before or have next to zero experience, I was just facetious about quitting healing or tanking, there could just be no spots left for them or they want to do non-standard comps. You want to prog ultimates fast in pf? Play a support, in the rare occurrence those are taken then SMN autopilot baby.
Being able to perform adequately without even looking at a guide, requiring zero experience, casts?, zero knowledge of cooldown management, MP management, 2min sync, while being extremely tanky is SMNs bread and butter. It really is just a healer without having to worry about keeping people alive.