The core prob with Support isn't Gold or XP...
The problems with supports are:
Low skill-expression Redundant play patterns
I have been playing support for a few years now and not once have I ever thought to myself, "gee if only I was a level or two higher, my play experience would be completely different!" The issue with supports isn't a statistical problem, it's a design problem.
Every other role in this game features multiple champions with high levels of skill expression, champions such as Fiora, Yasuo, Gangplank, Azir, Katerina, Draven, Kalista, etc.
Besides Thresh (a utility support), who in the support role is able to exercise the type of adaptive thinking and planning that is required to fully express mastery of a champion, similar to the ones listed above?
More often than not, support is expected to fulfill a completely reactive role and in a game like league where it's more fun to be in the driver's seat, it's just not as fun of an experience for most. And don't get me wrong, I have fun playing the role of a helpful peeler, but that play pattern gets really stale after a few years, and I don't see new champions coming out that shake things up.
tldr: More resources don't make the role any less boring than it already is. We just need more tools than what we have in the current support pool, that's all.