In 2024. I belong to those 71%, i.e. I don't want Trump to run in 2024. But if he does and wins primary, I will fully support him and vote for him.
Same reasoning likely applies to you. You may not want Biden to have 2nd term. You prefer somebody else from D as next president. So, you belong to xx% voters who don't want Biden to run in 2024. But, by the 2024, you see Trump likely to be nominated and Biden is the only candidate from D who can beat Trump. You will vote for Biden.
Conclusion: It means nothing now if 71% or whatever percentage of voters don't want Trump or Biden to run in 2024. That is, it doesn't matter you want something. American presidential election has become a game. Once the game starts and you, the voter, are in the game, it will not be something you want before the game.