RC's are ultimately decided by witnesses. If ordinary users (as opposed to spammers or power users) are being constrained, we would be expected to increase available RC's and bear the increased costs of running a node.

If ordinary users need a delegation to get the required RC's to use the blockchain, we're failing.

Although perhaps if we really get big, the resource usage of an ordinary user will be much higher. In that case, we may expect ordinary users to need to own a certain level of stake or get a delegation.