There are several differences between these two periods of 400k daily transactions as well. The most obvious is that mempool is nowhere near as congested and blocks are bigger, with more transactions... suggesting that blocks are more efficiently filled (thank you SegWit).

With Lightning as well, we're seeing people take more txs off-chain (not to mention higher use of external wallet-to-wallet transactions that are completely off chain. OTC volume is also climbing, again, off chain.

So we're seeing 400k, I wonder what we're not seeing?