When thinking about whether 2m social distancing is enough when coughs and sneezes can travel viable infected virus much further, my understanding is that governments care about onward transition rates. If on average an infected person infects less than one other person it will eventually fade out.

So the question is does the 2m separation push the averages towards that? I would think it does. Partly because the number of people within a blast radius of a cough or sneeze is much lower, and secondly the probability of infection drops with distance.

Social pressure that then drives coughing and sneezing people home in a social distancing environment probably reinforces the effect of reducing transmission rates.

Is it enough? That will have to be measured and analysed probably much later.