The main reason behind this is not to eliminate anonymity, it is to eliminate the competition. They
will come up with some sort of excuse to just ban Bitcoin and not other Crypto currencies that adhere to their criteria. The government backed Crypto currencies will get the edge and they would get
a good advantage. The reason why they stalling with regulation is, because the currencies they want to support are not fully developed yet. Once these
"private ledgers" are ready, you can bet your bottom dollar, they will try to ban all the other Crypto currencies that does not adhere to their
requirements.
![Angry](https://bitcointalk.org/Smileys/default/angry.gif)
But that's my point, if there's no annonymity (and you can't use BTC for anything illegal + you pay taxes on trading etc) there's no excuses left to ban BTC. Therefore, if that was the goal - they'd be trying to ban it now alltogether, rather than just trying to take out the annynimity.
There will be no 'government backed cryptos' (in the form as we know it). No government would voluntarily restrict itself from being able to create money at will. It would require changing the current financial/money issuance system. The best/worst you can expect is governments using private, closed "blockchains" for managing and distribution fiat money. But that's far from 'government cryptocurrencies'.