The claims that is is privacy preserving are deceptive, and in my option constitute an act of intentional fraud on the part of its creators -- the fact that people are deceived by the privacy claims is clear in your comment: You ask why would the banks adopt something private. The answer is: it isn't.
Its existence is justified under a fairytale model of how the world works-- a false belief that actually anonymous payments are unlawful and that their compromised alternative is the best possible. In the path of doing so, they not only falsely sell a system with compromised privacy as private, but they also help bring about a dystopia where privacy is unlawful in much the same manner that doing business with companies that refuse to accept cash does.
It would be fair to say that its an upgrade to privacyless systems-- because it doesn't attach the sender's identity to the transactions themselves--, but to characterize it as a private or privacy preserving system is a lie.
Moreover, I don’t know in which part of the world you live where private on-line payments are commonplace, but the only cashless payment options I tend to see are with bank transfers, credit or debit cards and payment processors like PayPal. My understanding is that compared to those, Taler gives payers privacy and doesn’t make things any worse for payees than they already are, which makes it an enormous step forward for privacy. Perhaps I’ve missed something, because saying it helps bring about dystopia when it only strives to make things much better than they are right now seems terribly out of touch.
I find this objectionable, but not at all deceptive or manipulative.
People hear that it's private and -- unsurprisingly-- think it's private! :P In my view it's like to Apple's proposed content scanning in end to end encryption that applies a lot of additional cryptographic complexity with language that suggests that it's protecting the user's privacy, but in reality the complexity is entirely there to undermine their privacy (in a somewhat selective way) and a far simpler scheme would give much stronger privacy.
I think it's analogous to promoting a key-escrow cryptosystem as "communicate privately!"-- both in terms of people not getting the privacy from it they would expect and helping to bring about a world where actual privacy is unlawful. The privacy problems of Taler are essentially identical to those of key-escrow: even if you don't have any fear of 'lawful' access, any access that exists may be abused. The only reliable solution to the security/privacy problems is for the access to not exist unless that is literally impossible. But it's clearly not impossible, as many people use more private systems than taler every day including in Germany.
Taler is strictly less private and considerably more complicated than a basic chaum-cash token system-- which actually provides the privacy people expect it to have. So it's not like I'm suggesting blockchain mumbo-jumbo is the only alternative. :)
https://github.com/jlopp/physical-bitcoin-attacks
That is objectively, justifiably classifiable as manipulative and destructive.
To clarify: I assert that taxation and a functioning state, and the safety and security of the users of an online currency are absolutely not incompatible with one another—and I'm not even implicitly asserting that the definition of a "functioning state" is some kind of weird ancap impossible libertarian ideal.