The concern he was raising here was not about their side effects from the drug on people who would otherwise have been asymptomatic, it was that they were only monitoring people with active symptoms, which tells us nothing about whether or not the people who received the vaccine even gained sterilizing immunity or whether they are still spreading the disease asymptomatically.

I don't think this is what this was saying, because of in the context of where that is situated in the article. It says nothing about that subject in that part of the article.

Meaning we literally do not know if those people are capable of being infectious, if they are immune how long that effect would last, or whether or not they are still spreading the disease even if they are not experiencing symptoms

Which is a concern that surfaced in an entirely different section of the article and which I addressed.

This is a not at all a silly concern if you’re talking about rolling it out to the entire country where most of the spread is happening because of asymptomatic infections and don’t know the answer to whether or not the vaccine stops that from happening.

The reason I said it is silly is because the article states there is little to no public health benefit, and the only benefit is to the individual. If you do it to most individuals in the country (especially venerable groups), that's no longer just an individual, that's the definition of a "public health benefit". It's like saying "well, I found a cure for cancer and I'm giving it to everyone but it won't stop other people from getting cancer so it's basically only good for the individual and not public health". Like, yeah, IF it turns out that it doesn't stop the spread (which we don't know and not knowing is different from knowing it doesn't), that's not as good as we'd hope, and it won't stop COVID as fast as we'd want, but it will still be an extremely significant public health asset. The only argument I could see here is "maybe another vaccine would be able to stop the spread and so we should wait to see that". The issue is, I seriously doubt we'll see any credible results about whether any vaccine stops the spread any time soon, because it is a genuinely hard test to run in an appropriately controlled environment and we don't have the luxury of time. If it is safe and it saves people, people should do it.