Poor people are supposed to benefit from inflation because their debts can be paid back with money that's worth less. Meanwhile savers are supposed to use investments, not cash.

The US Dollar can be adjusted as needed, according to the needs of society (such as population growth and economic expansion). It's backed by the force of an entire military, and is also backed by an interconnected mesh of dependencies across an entire global economy.

If the US government fails so spectacularly that the US Dollar loses value, do you honestly think that the internet will even be working at that point? And without functioning internet, there won't be anyone mining bitcoin, which means that control of the blockchain will be easily seized by whoever has control of the largest mining pool. This would very quickly result in complete devaluation of Bitcoin (but not before whoever took control would be able to cash in a LOT of money).

If we had truly decentralized peer-to-peer internet (think ham radio over mesh with millions of portable devices or something) with truly peer-to-peer DNS and full encryption, and no centralized control, then MAYBE bitcoin might have a chance if the government collapsed. But we don't. So (at least for now), the idea that Bitcoin would function as a viable currency in that scenario is a giant joke.

It's true that the US Dollar is inflationary (while Bitcoin is "deflationary"), but that is by design to drive economic growth. Simulations (and history) have shown that with a slightly inflationary economy, people are more likely to spend their money instead of holding onto it. This causes a constant cycle of spending and earning, driving more goods to be created, and causing more people to do more work.

Deflationary economies, on the other hand, often result with the economy stagnating (because people are more inclined to just hold onto their money instead of spending it). You could argue that this is better (because people like the idea of their money gaining in value over time), but to make that argument, you would have to prove that economic growth is a bad thing.

Alternatively, perhaps Bitcoin is just another payments system with a different set of tradeoffs. Namely - it has a preset supply schedule that you can easily see, which won't be affected by political whims, or change at a moment's notice.

Sure, and the same could be said about practically every other crypto-currency.

As to the idea that it isn't subject to whims or political stability, I would argue that one merely has to look at the history of Bitcoin's price to prove that statement is false. Bitcoin's price is highly reactive to political news and random whims of the market (as well as manipulation by bad actors).

I'm not saying that crypto-currency doesn't have its place. I'm just pointing out that a lot of the fundamental principles that people swear by when it comes to Bitcoin are flawed.

Keep in mind that the poor hold fewer units; this is almost, only subtly different from, the definition of poor. In fact, the poor often hold negative units, in the form of debt.