These arguments are uniformly terrible. Let's go over them point by point.

> COVID-19 immunity is a mystery

No. It's not. Recovered people are almost certainly immune. There's evidence that's come out recently to actually empirically confirm this, but it's also how almost all diseases work, and so it's a super reasonable prior in the absence of evidence. This whole "we haven't positively proved it, therefore we have no idea" position that's being taken in some corners of the healthcare community is ridiculous, dangerous, and wrong.

> Serological tests are unreliable. The volume of testing needed is unfeasible. Tens to hundreds of millions of serological tests would be needed for a national immunity certification programme.

Some serological tests are unreliable. So use the reliable ones, problem solved. The US is doing hundreds of thousands of tests a day. That's enough for this program to work.

> Too few survivors to boost the economy.

This may be true in some areas, but it's certainly not true in NYC, where 20% of the population has been infected already. Even if it doesn't boost the economy, it'd allow freedom of movement to people who have recovered - that seems like a valuable thing to me on its own.

> Monitoring erodes privacy.

No it doesn't. Give someone an immunity certificate. If they get stopped outside when they're not supposed to be, they present it to the police and go on their way. Just like a drivers license or any form of identification now.

> Marginalized groups will face more scrutiny.

No. We do not need any extra monitoring to do this. Just take the current system with its current restrictions, and lift the restrictions for people with a certificate of immunity.

> Unfair access. With a shortage of testing, many will not have access.

First of all, unfair access is a choice. Design the system so it's fair, if you're worried about that. Second of all, unfair access is not a reason to deny access to everyone.

> Societal stratification.

This is literally the point. To stratify by recovered/immune. If you actually want to get into this, traditionally marginalized groups have been disproportionately infected by this virus, which means they will be disproportionately granted immunity certificates. If anything, this will stratify in the opposite way from 'traditional' stratification, and that seems like a fine thing to me.

> New forms of discrimination

This is just a restatement of the last two points.

> Threats to public health. Immunity passports could create perverse incentives. If access to certain social and economic liberties is given only to people who have recovered from COVID-19, then immunity passports could incentivize healthy, non-immune individuals to wilfully seek out infection — putting themselves and others at risk

Driver's licenses create perverse incentives. That's not a reason not to issue them. If someone infects themselves with covid to get an immunity passport, that's fine, we'll just get to herd immunity that much faster.

Remember, immunity passports aren't putting more restrictions on anyone. They're just lifting extant restrictions on those who have recovered. This idea that it's going to erode privacy or rights is such a crazy false choice I don't even know where to begin. The reasoning in this article is just so, so bad.