I think that many of your intuitions will prove to be correct, after the hysteria dies down.

It was actually quite surprising to see many public health experts propagating the fomite and droplet narratives as primary modes of transmission. Numerous past researches of respiratory pathogens have indicated aerosols as possibly the most important form of spread (1, 2, 3). In fact, research in the 1930s and 40s "demonstrated that airborne particles can remain airborne for as long as one week after initial aerosolization, and suggested further that these particles likely remained airborne for much longer" (4).

Consequently, the empirical data that has emerged over the course of the pandemic supports the idea that masks have very little impact on the spread of respiratory pathogens (which was reflected in most trials and governmental guidelines up until sometime in the summer of 2020) (5). Aerosol penetration of cloth masks, which are being recommended, is around 97 +/- 3% (6).

Your comments relating to fecal aerosols are probably also correct, and research has been published to support that. One study suggests that numerous individuals in multiple flats were exposed via the plumbing system in a high-rise in China (7). The same study references a similar situation taking place during the SARS-CoV-1 outbreak.

1. "Routes of influenza transmission". https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5909391

2. "Aerosol transmission of influenza A virus: a review of new studies". https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2843947

3. "Transmission routes of respiratory viruses among humans". https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7102683/?report=reader

4. "Aerobiology and Its Role in the Transmission of Infectious Diseases." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3556854/

5. WHO. "Non-pharmaceutical public health measures for mitigating the risk and impact of epidemic and pandemic influenza". https://www.who.int/influenza/publications/public_health_measures/publication/en/

6. "Comparison of Filtration Efficiency and Pressure Drop in Anti-Yellow Sand Masks, Quarantine Masks, Medical Masks, General Masks, and Handkerchiefs". Aerosol and Air Quality Research. aaqr.org/articles/aaqr-13-06-oa-0201.pdf

7. "Probable Evidence of Fecal Aerosol Transmission of SARS-CoV-2 in a High-Rise Building". https://www.acpjournals.org/doi/10.7326/m20-0928