Bitcoin and others will never succeed because they are too friendly towards illicit behaviour. Taler seems to strike a genuinely interesting and ethical balance here.
The idea that this sort of activity is able to be decoupled from surveillance is one of the more unfortunate delusions in politics.
That said, I do agree that governments care about the contents of the purchase; around here, all sales must be invoiced with certified software, and a copy of all invoices issued must be delivered monthly to the IRS by businesses. As the buyer, you can opt to remain anonymous, but they're trying to push people into not doing so.
Is cash also unethical because the government doesn't have absolute surveillance on cash spending?
What the project claims is a "liberal" tool can very easily become a very unethical tool of oppression.
I doubt various governments can do a whole lot about it, which means it's likely to succeed eventually.
Bitcoin will never (fully) succeed because it's too complex for the general public.