You are right, winners don't stand on a "lectern."
They stand on a "podium."
podium - noun
UK /ˈpəʊ.di.əm/ US /ˈpoʊ.di.əm/ plural podiums or podia
A raised area on which a person stands to speak to a large number of people, to conduct music, or to receive a prize in a sports competition. "Tears ran down her face as she stood on the winner's podium."
Here in the United States anyway, people are constantly using the word “podium” (what you stand on) to refer to the “lectern” (what you stand behind). The reverse, not so much. Confusing these two words erodes the richness of the language. We’re on the verge of having two words for “lectern” and none for “podium.” - Daily Writing Tips By Maeve Maddox
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