Instead of thinking about what bitcoin&co. save for a single average person (not that much in comparison to e.g. gold), think at bigger scale: It forces states

Instead of thinking about what bitcoin&co. save for a single average person (not that much in comparison to e.g. gold), think at bigger scale: It forces states to be even more mindful about what they do with their currency. Because, states have a lot of ways to prevent people from starting to avoid their currency. In particular they can increase tax on everything, such as real estate, income, or just wealth in general. However, taxing bitcoin (or even monero) is so much more difficult, that it can act as a sort of regulator - similar to gold, but even better in this point.