I simply hear to proponents' testimonials.
So far, the prevalent stories have been about servicing people living in countries suffering from hyperinflation, which is just as easily done with a foreign currency.
Another common point is the promotion of smart contracts. It seems to me that these tools are still anecdotal, and don't really provide a significant competitive advantage compared to standard contracts. Besides, cryptos not using pow and incorporating good tooling are much better suited for that.
The decentralized nature of the ledger is another common selling point, but proponents don't really tie it to a material benefit.
Other impacts, usually not really promoted are its support to illegal activities such as digital racketeering, money laundering, etc. For instance, the financial aspect of ransomware is usually supported by this technology.
If you feel I have missed some impacts, feel free to point them out.