Most ppl here just keep giving reasons why the claims being examined are wrong, but that is not what a steel man arg is ppl!
Regarding the first argument:
When the opportunity presents itself, governments could seize it and punish examplarily someone who committed a horrible crime who somehow used Bitcoin and make them the "face" of Bitcoin.
Governments could sponsor campaigns about how "Bitcoin is black market money, that is used to buy/sell illegal things like children and drugs, and how it is used by terrorists/supremacists." And encourage people to rat on merchants who accept Bitcoin. Who could be punished in varying ways, depending on the country they live and their newly enacted laws... Banking on social stigma to stifle adoption could make finding vendors accepting it sporadic and shady. Making the experience subpar with their CBDCs.
Governments could pass laws aiming to regulate open source software and in it include a *very* ambiguous paragraph that would amount to "coders/contributers are responsible to how the software they publish online is used." (I am looking at you EU...) This could allow them to - very selectively - go after the "people who make the black market possible. We were so close to ending it... 😞".
They could also force Apple and Google to ban apps from their store. And Github and Gitlab from hosting projects related to bitcoin. Then they could spread disinfo saying that downloading apks from Fdroid and self hosted git servers are dangerous and could have viruses. They could make it illegal to host files related to certain *forbiden code* and ban those IPs at the country level, as well as the IPs of popular Lightning networks. Perhaps even sue people hosting it. Sure most ppl who use Bitcoin today could find their way around it, but this could certainly impact mass adoption.
The goal being to make using it unreliable/annoying and give it a feel of illegality.
Countries could also selectively ban encryption, and while they would never be able to enforce it, by giving themselves the ability to issue permits for ppl/companies to use it, they would be able to use it to justify action against people they view as problematic.
I would address this by saying that:
While that could have a profound effect, those actions wouldn't come without a price on government. They would need to become significantly more authoritarian which would fuel pushback and protests.
Tools like Tor exist that can ensure that people developing and contributing to the tech remain anonimous. Plus it would be very hard to enforce those measures, and it would be too costly too.
Even if GOV manages to have a smooth roll out of their CBDCs, things like inflation, their ability to put an expiration date on it, their ability to outlaw the use of CBDCs for certain things deemed bad will at some point push people to see the value in Bitcoin and how tyranical their government has become.
Further, ultimately none of those tactics allow gov to control Bitcoin (the only way to end it), nobody can. They can only compete against it, and while they can slow adoption and to some extent sabotage it, at the end of it, what really matters is that their product (CBDCs) is inferior, and in time Bitcoin will succeed.