Your rebuttal scenarios are weak, of course in this fantasy scenario some cars will still be allowed. But yes I do agree about butterfly effects, like in this scenario: https://www.bbc.com/future/bespoke/made-on-earth/how-the-cov... or https://archive.is/0inYa

Pandemic happened -> Europe went to lockdown -> Restaurants, hotels closed, weddings cancelled -> a drop of flower sales -> Kenyan flower growers suddenly find themselves out of work and out of income (plane-loads of flowers get flown everyday from Africa, M. East and S. America to Europe)

Yeah it was probably okay sailing for rich countries that can conjure up debt and give their citizens some relief, but how about for the poorer countries? India had a lockdown and day-wagers had to walk thousands of kilometers home, and the PM's response seemed to be "Not my problem!"