To be fair, the Olympic weightlifting movements in their current form are pretty leg-dominant. In the past when there was a third event, the clean-and-press [1,2], athletes needed a lot more upper body strength.
[1] https://www.youtube.com/watch?v=3nJrYPVJ88M
[2] https://www.youtube.com/watch?v=Z4l6eH-lmMA