You read the article?
Szabo doesn't make any sense here:
Any commodity that can be stored and so traded can be used as store of value that will render the owner immune from the perceived or actual risks of holding a floating currency.
First of all, just about every currency is a "floating currency" unless the entire supply has been entirely mined from the closed ecosystem and you no longer have to worry about cost of production affecting value. But even then, you're still governed by people's sentiment for how much they value that object to trade their goods and services for vs bartering with something else. Everything about the currency is going to be floating in one way or another.
Secondly, bitcoin having a potentially wildly floating cost of production is one of it's greatest weaknesses and one reason it's not a store of value. A wildly volatile to the downside cost of production is a black swan event in itself and would render confidence in that asset to nothingness. If we lived in an open ecosystem, which anyone who claims we will be mining asteroids for metals does, then the cost of production and it's ability to not plummet is the main factor that makes gold a store of value at all. If you live in a closed ecosystem it's not that big of a factor since you're bound by supply.
As for bitcoin, the fact that mining NEVER ENDS is exactly the equivalent of using gold as money while being in an open ecosystem. If cost of production craters, you're screwed. This can happen in bitcoin easily. The act of previous holders just hoarding their money and refusing to sell low doesn't help because the network is officially dead in the first place if there's no mining fees to siphon off at this new lower cost of production, so the fresh lower cost of production coins drag everything else down with it.
Your first paragraph tells me you cherry picked some statement and stopped there.. or you are incapable of understanding what he wrote. Commodities and fiat currencies are thougjt of as fundamentally different stores of.value concepts since gold standard was dropped as dipicted by 2 telltale events.
Bitcoins cost of production is rising exponentially and thus.if thought of as a commodity its store of value also should rise with it.. if.thought of as money it has higher utility than its predecesors and thus more valuable either way. I will trust in math all.day long over trusting central banks or having to lugg around tons of precious metal that will be stolen if shtf and bitcoin wasnt around.
Now show.me besides asics when cost of production shifted enough to make noise to the downside? That is the point to create energy more efficiently.by linking incentive via block reward. Its a direct metric for stability as if a new way to form emergy is dicovered they will be rewarded but society benefits the most.. it classifies as a form or ideal money and multiple times better than gold ever will. Afterall doesnt it all boil down to.energy anyway?