I don’t think your extreme examples have much to do with what Ionescu is saying here. He’s talking about a inherent human condition regardless of the standard of living. Can’t say I agree to it, because he generalizes far too much, but there sure are many people I’ve met over the years how qualify to have those feelings.

a) Extreme? This year, more than 1 billion people will go hungry. One billion individual humans who will not know whether they will have enough food to live through the next days. It’s sad, but this kind of situation is actually pretty common.
b) I’m also drawing on the rest of Ionesco’s work and thoughts here, and his general opposition to any kind of political art. (He despised Brecht, for example.)

Israel has concentration camps? For serious? Or are you just making some kind of weird metaphor?

If you look at the (walled-off/fenced-off/guarded) areas where the Palestinians live, the term “ghetto” doesn’t really seem enough…

Wealthy men have bad days and concentration camp prisoners have good days.

Yeah, but I think there’s a huge difference there. “I have a headache today” and “I only got beaten up once today and they gassed someone else instead of me” don’t really even out, do they?

I will say this much. People adapt to situations, positive or negative. Wealthy men have bad days and concentration camp prisoners have good days. The elderly develop a tolerance for the pain in their joints. I’m inclined to go so far as to say it averages out to zero. What isn’t so relative is freedom. Freedom to live, to express, and to choose.