To some degree the behavioural argument about the negative impacts of masks in public is speculation, but there is obviously a common sense reasoning behind it.
But ultimatly, your statement is speculation too. It doesnt follow from masks having certain effects on a very specific micro level to them actually having any significant impact on a macro level.
If masks truly have a significant impact, then why havent this been more obvious in the death counts between different countries?
In a YouGov survey in june 2020 the number of people in the nordic countries who said they wore masks were extremly low (I think 2 % in Denmark, Sweden and Finland and 4 % in Norway). The same numbers in other countries were 35 % in Canada, 54 % in France and 59 % in USA.
(https://www.nytimes.com/interactive/202 ... k-map.html
Sure, the numbers have probably changed since that. But have the general attitude towards masks done? In Sweden the vast majority have never worn masks, I was in Copenhagen the other day and it seemed to be the same case there (as was it when I was there the last time in 2020 despite a law dictating that had to wear masks in public transport). These numbers to me seems to suggests that masks in public have virtually no impacts whatsoever?