I think it is a very reasonable policy to instill during a period of uncertainty. As you point out, we have to take a precautionary approach. I would say that the variants of concern—a few months ago and to a lesser extent now—pose a significant threat.
When I say “to a lesser extent”, I meant that because we have a greater understanding of what it is they do and the threat that they pose. I would not suggest that we have a full understanding of this, but I think we can use our understanding of this and certainly our understanding of how the vaccines protect us against the variants of concern and the role of variants of concern. We can use that information to help determine what the most appropriate policy is.
In the face of an unknown threat, I think it is very reasonable to take whatever measures you have to protect yourself. We've seen other countries do that rather successfully. We've seen, for example, Australia, New Zealand, many countries in Europe and Israel take the same approach. It's a very reasonable approach and it adheres to the fundamental public health principles.