Such techniques have proven to be very effective at preventing hospitalization and death for SARS-CoV-2 [1][2], yet you will rarely find anyone advocating for them.
The papers I've cited are some of the most highly cited in the literature, with world-wide support from experts at top institutions who are actually treating COVID-19 patients.
These alternatives to vaccination are likely more palatable for the anti-vax crowd, and can help prevent over-utilization of precious medical resources.
[1] Pathophysiological Basis and Rationale for Early Outpatient Treatment of SARS-CoV-2 (COVID-19) Infection https://www.amjmed.com/article/S0002-9343(20)30673-2/fulltex...
[2] Multifaceted highly targeted sequential multidrug treatment of early ambulatory high-risk SARS-CoV-2 infection (COVID-19) https://scholarlycommons.henryford.com/cgi/viewcontent.cgi?a...