Oh I’m not arguing it’s a hot temp and exerting yourself in those temps is very much a death sentence; especially without water. I’m saying that many people in the world have lived through those temperatures. Research studies have a way of making things a bit more dire than what is normally human survivable, probably for legal/medical moral reasons.
The US military definitely has rules against 40+ WBT and state how many hours of work per hours of rest we could have in high temp+humidity levels. However, I, and anyone who had to deploy or live in East Africa (like Djibouti) or the Middle East can definitely attest, 50WBT is survivable for 8 hours days. Again, not talkin’ elderly or sick persons.