For airports specifically, look for an official taxi stand with an attendant. I flew into Santiago about 15 years ago to spend a month in Chile and didn't think twice about being scammed. Everything I read said that Chile and (modulo city life) Santiago had and still has relatively low prevalence of crime and corruption, by any standard. While I'm always wary of pick pockets and other random street crime, some places you tend not to worry about organized or systematic criminal rackets wrt mundane activities. So I just jumped into a cab at the airport without looking for a taxi stand.

Recently I came across a forum where people were discussing a supposedly well-known and long-time scam at the Santiago airport involving taxis picking people up and extorting money. So perhaps I dodged a bullet (or an adventure) at the Santiago airport. Of course, there's no guarantee an attendant wouldn't be in on the scam, but the goal here is reasonable risk minimization, otherwise your only real option is to hunker down in some Japanese or Swiss suburb.

Reminds me of how scammers will intentionally use bad grammar/spelling in emails to filter out "low conversion rate" prospects.