If we assume all measures work, then we prove all measures work. And of course, we ignore the time dimension:

A mask mandate, combined with complementary public health measures, could have a $1 trillion impact on the U.S. GDP, says UCLA study.

Source: U.S. Mask Mandate Could Add $1 Trillion To GDP, Says UCLA Analysis – Deadline

The study refutes itself:

By the end of June 2020, nearly 90% of the global population lived in regions that had nearly universal mask use, or had laws requiring mask use in some public locations, and community mask use was recommended by nearly all major public health bodies,” Howard said. “This is a radical change from the early days of the pandemic, when masks were infrequently recommended or used.”

If 90% wore face masks in June of 2020, then why did we see 10 to 20x more cases in high compliance areas months later?

This study, like all such studies, ignored the time dimension. Nearly everywhere, given time, has ended up in roughly the same place. 

Public health has turned into a faith-based religion. If you believe in masks, you will achieve salvation!

At this point, its lock downs and face masks forever. The elite politicians and public health experts will continue to travel and attend their parties.