Interesting, Kam.
Unfortunately mostly the only people who have taken the virus seriously are those who were in or near a significant outbreak. The Wuhan/Hubei outbreak was a kick in the pants for China to become serious. Very, very few places took strong measures before the virus hit them -- only Vietnam, HK (but with the China outbreak in their backyard), Taiwan, New Zealand as far as I know. All hugely successful too.
Only after the scary and devastating NYC/NY metro area outbreak NY and NJ got serious.
Were temp checks ever implemented in the US? During the 2 month lockdown here, most food stores and such did temp checks before allowing you in. Was pretty common for office buildings once the reopening started up. Etc.
I have no idea how useful this was, though it certainly is useful at the airport.
I think the 6' rule was more of a distraction than a help in the US. People were inconvenienced and felt like they were doing more than they were to stop transmission. China didn't do this at all.
I posted an article about the old and faulty science behind that distance rule last week.
Shanghai hasn't let anyone on the subway (or bus/plane/train) without a mask on since Jan 23. I will agree it was easier to wear a mask in Feb/March than in June/July. Though by then mask wearing was already pretty optional in SH.