We know that viral infections colonise the body by reproducing inside of target cells, then releasing the viral payload when the cell dies, which goes on to infect more target cells.
We know that a virus like COVID-19 spreads to other hosts in cough droplets or even in the air.
We also know that COVID-19 attacks the lungs at multiple sites of infection. (https://www.usnews.com/news/health-news/articles/2020-03-22/covid-19-lung-patterns-show-few-clues-for-treating-pneumonia)
Does it not stand to reason then, that coughing can encourage the spread of viral payloads from one site to many more sites within a person's lungs, effectively 'metastasising' the infection and forcing the immune system to fight it on more fronts?
Would it not be beneficial to avoid coughing when possible, perhaps using cough suppressants like levomenthol to open the airways and keep the infection localised to as few sites as possible?
Perhaps the infection could be cleared away naturally by the cilia, using expectorants like guaifenesin to encourage production of more viscous mucus?