The context is obvious. Anything that reduces R0 is a good thing. As even the most scientifically illiterate Rossi devotee should be able to understand...
For example, lets say masks only reduce transmission by a measly 1% per day.
At the end of the year we will see 37 times less death, hospitalisations etc etc.
Marginal gains work.
Well, I agree, but the real situation is more complex than a single exponential.
With delta it now seems pretty well impossible to stop endemic COVID - even in vaccine-friendly countries like the UK. In which case controlling the infection is about achieving enough natural immunity for a minority unvaccinated or high contact segment of the population. In this context a small change in R spreads the epidemic peak out, but does not necessarily reduce total infections. However spreading things out is valuable:
- It reduces peak hospital demand
- It allows time for better treatments and more vaccination
- It potentially reduces disease burden by making the typical initial dose smaller, so harm for given number of infections is less.
In the UK we seem to have R=1 with 60% of whole population vaccinated. Although that is a combination of natural immunity and vaccination it is important to realise that natural immunity does not prevent transmission, so vaccinated those who have been infected before affects the overall course of the pandemic, and therefore high many people die, even though it has a smaller effect on personal outcomes (We do not have a lot of information on fraction of serious cases amongst those who have previously been infected). It seems quite likely that the only way to get COVID rates right down is vaccination + a bit of natural infection. Of course if the infection is after vaccination, the burden is much much less.