Total stunt in front of cameras to try to strong-arm Zelenskyy into a deal that gave him no guarantee of future securities in exchange for Ukraine's mineral wealth. Zelenskyy was trying to express his concern over past agreements' terms not being met and how that could be the case again, meaning they would have given up their wealth for nothing.
Trump and Putin do not care whether that wealth is gained by America or Russia because they would share it indirectly.
All Zelenskyy was doing was trying to negotiate in a calm, professional manner. Vance and Trump wouldn't even listen to him without demanding he thank them for what past administrations have done for Ukraine. Then they changed the subject completely and got very loud because they were disappointed that Zelenskyy was not easily pressured into a bad deal where Ukraine is the only one to make any real and lasting compromises with no guarantee of prisoners returned or backing if Russia starts it all up again.
It's clear the two who were yelling had lost control of their plan. And it's clear Zelenskyy and Ukraine cannot count America as an ally under it's current regime.