^ 13000 tx every 10 minutes would be really cool, and Segwit making leaner txs still resulted in full blocks, I always expect to see this as the gradual way forward -- upgrades that result in leaner, more efficient txs, rather than just widening the bandwidth.
Then again, when I was in the 1990s thinking everyone would focus development on making better compressions for leaner data formats... spent hours on websites making sure they were as small as possible (in bytes). It went the other way (in my view) -- bandwidth just exploded, and people didn't care about efficiency anymore.
In order for Bitcoin to succeed, blocks must be full.
If blocks are never full, then there is never a reason for a transaction to pay more 1 satoshi in fees. As the subsidy is reduced, fees become more important. So at some point, full blocks will be necessary in order to ensure that the revenue is high enough to discourage a 51% attack.
Changes that attempt to prevent full blocks would directly impact the security of Bitcoin.
I may not see this is a hard rule, but I certainly can find some space to agree that the entire structure of returns for those securing the network (miners) was designed to ensure there was always incentive to mine. Coin generation at first (the subsidy as many say), then later the fees.
People give a lot of credit to adoption, commercial interest, recognition, for price. And credit due, but I still feel that the actual financial cost of securing the network, and the necessity of profit for the miner, still play that hard economic backbone.
By design, isn't it?