I think part of the benefit of everyone wearing masks is that there is more value in limiting the distribution of virus laden particulates from the source, ie t

I think part of the benefit of everyone wearing masks is that there is more value in limiting the distribution of virus laden particulates from the source, ie the infected persons mouth or nose, at least to an extent. That is best done when an infected individual has a mask on. Additionally, if we assume that wearing a mask limits spread, then unmasked individuals overall are a higher risk for receiving infection. Therefore community risk is higher. That's how we end up with a calculus that determines that impinging individual liberty (requiring masks) has a net benefit (limiting overall community spread). I guess a similar analogy might be: driving half the speed limit might in a weird sense feel like you're protecting yourself from harm in an accidental if else someone drives too fast, but the better policy would be that both directions of traffic maintain speed at or under the limits. Again, this is an instance where we limit individual freedoms when there is a perceived net benefit to community safety.