Part of the cape and aura stuff being locked by level was actually a performance concern- the devs figured if everyone in the game was wearing capes and auras from lv1 then computers would melt in crowded areas.
In 2004? They were right. It happened a lot anyway at Icon, which was crowded to the brim when it, capes, and auras were added.
By the time the game went f2p though, standards had gone up enough that it wasn't an issue anymore. And then if you didn't unlock or buy cape/aura access for lv1s, well. That's your own fault.
But I totally remember people complaining about the performance hit capes and auras caused.