ago. They gave stratified data for various age groups, for which the IFR varied widely. It was lower than .23% for most age brackets, much lower for the younger brackets and much higher for the higher age brackets.
TigerMatt had said that he had seen a .2% IFR and I bumped that up a little bit to .23% as a margin of error.
Estimates do vary quite a bit. As you say, estimated IFRs have been dropping significantly over time. Some of the discrepancy between countries was likely that the CDC and WHO had been trying to keep doctors from prescribing Hydroxychloroquin and Ivermectin and discouraged pharmacists from filling prescriptions for them for Covid until recently. Many other countries were using them with very good success. Some doctors here were using them despite the CDC guidelines also with very good success.
Fwiw it was reported on Oct. 2, 2020 that:
"An estimated 750 million, or 10 per cent of the world’s population, have been infected by Covid-19, World Health Organisation (WHO) official Dr Mike Ryan has said."
https://www.irishtimes.com/news/ireland/irish-news/covid-19-world-in-for-a-hell-of-a-ride-in-coming-months-dr-mike-ryan-says-1.4370626
At the time there were 1,032,733 covid deaths reported worldwide.
1,032,733/750,000,000 = 0.001377 = a .14% Infection Fatality Rate