Did research. So summer olympics are every 4 years, meaning 3 off years between
The world athletic championships are biennual event happening the year immediately after and the year before the Olympics so:
2015: world athletic championship
2016: Olympics
2017: world athletic championship
2018: OFF YEAR (will comment below)
2019: world athletic championship
2020: Olympics pushed to 2021
2021: world athletic championship pushed to 2022
2022: OFF YEAR
2023: world athletic championship
2024: Olympics
So the middle year is usually an off year. In 2018, they held the inaugural athletic work cup, but only hosted 8 countries. Ans supposedly, it was a flop. In my post above i wrote that it seems like a changing of the guard based off the thumbnails. But really, the 2018 WAC flopped because big names didn't show (since their countries weren't part of the 8, or maybe even within the given countries. Not sure about the latter)