In addition to this, noderunners in the future (and some now) will likely be running Bitcoin heaters (free bitcoin mining from the perspective of you were gonna run a heat producing device anyway), and thereby this subsidy goes partly back to them. Using voluntary choice we can solve this problem with at least a partial, imperfect fix.

What I'm worried about is the question I posed: what are the incentives of miners, what would my solution do to them many steps into the future, how do we keep them incentivized to not spam the chain with things we don't want?