There is no true scarcity. I can create a clone of Bitcoin in seconds just by cloning a github repository and changing one line.
You might call it bitcoin all you want, but no actualy bitcoin software would be fooled. (You might trick some people, but fraud has existed long before computers).
It's a lot less expensive to reliably distinguish a fraudulent bitcoin from a fraudulent goal bar.
So even if you hold the position that there is no perfect scarcity because fraud is possible-- the cost, difficulty, and success rate of that fraud matters greatly.
If you want a string of bits that acts like bitcoin, you can replace it with Xcoin, for many values of X. You can even create your own coin which does whatever you need. You may not be able to replicate the network, which may provide some amount of scarcity, but it’s not the same as gold.
So-- silver? Sure silver oxidizes a bit, but the oxide is conductive too and silver itself is more conductive than gold! :)
I too was doubtful about bitcoin at first. It's just plain obvious now: first mover advantage, leading to the development of highly specific ASICs, with a side advantage of allowing the cross border trade of electricity when turned it into mining power. So if you live in some isolated place but with cheap energy, money!!
BTC is too big to fail. A success that can't be replicated or taken down as it was ignored for too long. Even more unimaginable now that it benefits some people who wouldn't let them happen without a fight, and who have the power and the money to give this fight.