Maybe tiny individual Covid-19 viruses can float in air,
not just inside droplets,
and tall people may be more at risk:

https://medicalxpress.com/news/2020-07-survey-aerosol-significant-covid-transmission.html

Sample quote
The survey analyzed by a team of data scientists in the UK, Norway and the US is one of the first to examine a wide range of personal and work-related predictors of transmission.

Taking both samples together, being tall more than doubled the probability of having a COVID 19 medical diagnosis or positive test for people over 6ft.

The data in both countries, argue the researchers, could suggest that aerosol transmission is very likely, with taller individuals at higher risk—something that would not be expected if transmission was exclusively through droplets.

And that, they say, is something that would not have been observed if downward droplet transmission was the only transmission mechanism.

Aerosols can accumulate in poorly ventilated areas and are carried by air currents. Droplets, however, are bigger than aerosols and are thought to travel relatively short distances and drop quickly from the air.

Though the paper is yet to be peer reviewed, the authors feel its implications on the debate over aerosol transmission should be made available to the wider community.
End quote