You can still withdraw some and spend it anonymously.
Given, you can't buy a house anonymously with cash, but can you do that with bitcoin?
https://commonslibrary.parliament.uk/research-briefings/cbp-....
Which makes it a bad store of value, but has nothing to do with its utility as a medium of exchange. We have lots of productive investments to hold value in between times it is is converted to cash for exchange.
Bitcoin is mainly attractive right now as one of (or an alternative to, depending on how you define “productive”) those, with a much higher average growth rate but also much more volatility than many of the other popular options.