What's orwellian or horrific about a cashless society? Sure, there are valid arguments against it, but that doesn't make it orwellian or horrific, this is just hyperbole.
It does. It wouldn't happen on day one. But, slowly, it would start creeping in. As someone else commented: what if, you buy some mega turbo sex toy 3000 and a couple of years later super religious orthodox government wins elections. What if the government decides that you can buy one thing but not another. What if you want to organise a little poker night with your old buddies and so on. Look what happened with the internet. Endless scare stories about terrorism, pedophiles and eventually mass surveillance is in legislation..
If a super religious govermment wanted to punish you specifically - they don't need your transaction history. They can put you in prison using a completely made up reason. Just look what the Russian government did to Navalny.
Scare stories about authoritarian governments that still somehow respect rule of law and due process are funny.
You're missing the point, it's not a case of "we've identified zirgs as someone we want to punish so let's go through their browser history to find a reason to do it" a tyrannical government hardly needs to go to such lengths as you point out. The nightmare scenario is you get people in power who say "we can make the world a better place if we just eliminate all the people who do X" and they have the digital tools to simply filter all citizens by X and get a nice big list they can hand out to the secret police.