Unless the problem of Bitcoin's high volatility is solved, it will never could replace dollars or FIAT.
Therefor, it could only be used to save us personally in future's economy only if we invest in it and hoping for its return in few years later if it is go smooth.
Even if it becomes stable, it will never replace the USD or fiat money. It was not created for that purpose and has no potential to do so. If satoshi created bitcoin with the intention of replacing fiat, I bet it would have disappeared long ago and we wouldn't be able to use it as commonly as we do today. The government will find every way to destroy it immediately if it challenges their power, don't be naive to think that because it is decentralized the government can't destroy it.
People like to hype about how bitcoin can help us avoid inflation, alleviate poverty...but honestly, I don't see how it can help us. Bitcoin is a highly volatile asset that is only really beneficial to those who know how to leverage and profit from it. Meanwhile, if we want to reduce inflation and end poverty, we need price stability, we need more jobs...and bitcoin cannot do these things. So it cannot be said that bitcoin can save us.