If it's been implemented to have bitcoin implant we cannot prevent that to happen, but since bitcoin is not yet adopted and government still not recognizing it as legal currency; that possibility is still a myth for now. Mark of a beast has been prophesized by the religions linked to christianity so that should be respected and those fears are silently deeping knowledge for all who believed, and established faith with it.
Yeah. Implants may not be prevented from becoming a reality soon. Perhaps, it won't be used in conjunction with Bitcoin since it is decentralized and governments would want a currency where they could have control over it.
But one thing for sure is that sooner or later, governments would make use of the blockchain technology for their own needs eventually leading the way towards the design of digital fiat currencies to be used with implants on every citizen. That way, there would be complete control of every transaction made on the country, adding transparency and reducing criminal activity such as money laundering.
Nevertheless, while implants may not be the most viable method for governments to keep track of your financial information, there could exist other ways to do so in a safe and secure form for anyone to use in the future. Just my opinion.