Dom's lips turned blue (allegedly, evidence from spouse)
SAGE is tasked with giving scientific advice, it is true. Reading the minutes is a sobering experience - on March 3rd and 5th SAGE concluded that there was no useful purpose to be served by cancelling mass events, on March 10th SAGE concluded that the evidence of a benefit of such a cancellation was marginal. Cheltenham festival started on March 10th and is now widely seen as a significant occasion of cross infection.
SAGE did consider mental health effects (and the risk, incidentally, of social unrest - they concluded that we are a docile lot :-) )
If you are not prepared to read and consider the Minutes of these meetings then I do recommend that you consider why the course of action you propose has not been adopted elsewhere on the planet. Surely if it is obvious to you......