In my opinion it's not about scaling... it's about survival. Today's 'default hashrate buyer' is the block subsidy. But like I wrote it won't be that way forever.

So why would anyone mine, except for reward? Either from subsidy or from transaction fees? Eventually nation states could and would mine and they might mine at a loss... but assuming that they would want and need to... there would likely be plenty of demand for blockspace anyway so the subsidy might not matter that much.

Bitcoin is what we make of it. The network is how people use it, and what they use it for. It's a 'use it or lose it' network and it's strengthened based on the speech and values of those who utilize it.

Mr Shinobi had a great post on this last year https://bitcoinmagazine.com/takes/bitcoin-use-it-or-lose-it