@kr I remain quite interested in this thesis, and I think your point has a lot of merit. Not trying to throw cold water on the observation. That being said....

I have to walk back my observation that, "no one cares about ... future transactions". Bitcoin miners' entire business model depends on anticipating future difficulty increases in order to plan their capital intensive expansion. So it is not the history of transactions that are important for predicting future growth, but the history of hashrate that can indeed be useful for predicting future growth. And it makes for a remarkable graph.