It's a pretty twisted definition of "essential" to include only the things that are definitely going to kill you if you go without and not to include the things that just might kill you.

Again, doctors and firefighters might look “essential” for a secular and technological society like ours (one where we’re afraid of death and where we value physical stuff that could burn) but that hasn’t always been the case. It still isn’t in many parts of the world.

In my parts of the world (Eastern Europe) often times the barber was also the doctor and the dentist (was called "felcer).

Unless things change over time, as such requiring new facilities. We didn't have nuclear power station inspectors (or regulations) thousands of years ago, so are they also non-essential?

> It still isn’t in many parts of the world

There are "many" places in the world were death is not feared and people are happy to see their stuff burn? Barring nomadic jungle tribes with no persistent possessions or home locations in the first place, which societies are you describing?

The fact that our ancestors commonly died of tuberculosis doesn't mean they where happy to do so.

So what? What does that have to do with anything?

you could say that... even sex-workers are more essential than doctors and fire-fighters.

You can say that, but you'd be wrong. That's the great thing about the internet. Anyone can say anything no matter how false it is, and they get to be on an equal footing with people who know what they are talking about.