When it comes to COVID-19 post-mortems, inquiries and audits, scrutinizing the ArriveCan debacle shouldn’t really be at the top of the list. But beggars can’t be choosers: If we can’t get a proper reckoning for having kept schools, summer camps, playgrounds, skate parks, golf courses and restaurant patios closed for reasons that look highly suspect in hindsight, even to quite cautious people, we might as well appreciate the feds getting pilloried for their spectacular failure in producing what ought to have been a very simple app.