Neither of your examples are tradeoffs. Both my computer and my phone are excellent at their jobs with little in the way of downsides. Bitcoin is bad at it's job with lots of downsides.

It only looks better than the alternatives if you live in a place where the economy is heavily mismanaged. If you're currency is only better than the absolute worst economies in the world don't expect all the people in better economies to look favorably on it. Except perhaps as a way to further exploit those in terrible economies by speculating in that currency and driving high volatility in it's value.

You keep moving the goalposts between "blockchain the technology" and "Bitcoin the currency". If you want a trustless auditable log, your best option is a blockchain. What's a better alternative?

Actually Bitcoin keeps moving the goalposts. First it's a currency, next it's a trustless auditable log. All I need for trustless is auditability. All I need for auditability is a public Merkle Tree. I fail to see what actual real world value the PoW and associated approaches actually add.

> You keep moving the goalposts [...] What's a better alternative?

> Actually Bitcoin keeps moving the goalposts.

Okay.

If you have a rebuttal, let's see it. Mockery is childish.

Still waiting for your rebuttal first.

There is nothing "trustless". Our world is social by structure, all our actions contribute to various kinds of trust. Blockchains aren't trustless they're just unable to internally express trust relationship: there is always trust in the devs, in the exchanges, in the miners, in the other holders. There are political events like "blockchain forks", protocol upgrade, parameter changes..

So much for the trustless auditable log. Btw "auditable log" is easy (eg certificate transparency), the hard part is deciding what goes in it.

Having said that you always trust something, you better do it consciously and run some real consensus algorithm like raft or stellar consensus protocol.

I think you've misinterpreted what Bitcoin's "job" is. Although the initial impetus was definitely to set up a new type of currency (something I'd agree it fails at) it has long since moved to behaving as a store of value, or a commodity. At this it excels.

The tradeoff GP is referring to is efficiency for security. If you have a distributed, "trustless" network you unfortunately have to trade your efficiency for more security.