I think we're already there. Multipolarity doesn't necessarily mean total cutoff from all dependencies (after all, the US is dependent on China in a lot more ways than vice versa), or that the US empire is completely defeated yet. It just means that they are no longer the only game in town, it means that countries have alternatives and the West is no longer able to completely dominate the rest and tell them what to do. It means that the West have lost their monopoly on technological advancement, on financial systems, on use of military force, their undisputed control over the global narrative, etc. In short, they are no longer global hegemons now that alternative centers of power have emerged.
What i am not yet sure about is when exactly this transition occured. One could argue it started as far back as 2008 with the global crisis of capitalism which China had to bail the West out of...or was it perhaps in 2013 when China launched its Belt and Road Initiative megaproject for economic integration outside of Western dominated institutions?
Was it maybe in 2014/2015 when Russia dared to defy the US by foiling their plans for Crimea and Syria, or in 2016 when it became suddenly clear that much of America and parts of Europe were no longer buying the liberal establishment's bullshit...or was it in 2020 with Covid which exposed western governments as morally bankrupt and woefully incompetent compared to China's?
Personally i don't know that i could pinpoint exactly when the transition started but i do know that Russia's intervention in Ukraine in 2022 was a watershed moment, and their subsequent weathering of the storm of the entire collective West's economic and diplomatic onslaught showed that we were now clearly living in a new world. One in which it is now possible to stand up to the collective West's bullying, to defy their tyrannical "rules based order" and not only survive but win and thrive. And the global south noticed this, hence all of the other sudden big events we have seen take place around the world since then:
France getting kicked out of West Africa, the Palestinian resistance entering into a qualitatively new phase of struggle, rapid expansion of BRICS, reconciliation between Iran and Saudi Arabia, the Yemeni blockade of the Red Sea, Iran striking a direct blow to the Zionist entity, Russia breaking the western sanctions regime on the DPRK, China becoming bolder in defending its own interests and no longer mincing words when it comes to the US's belligerent actions directed at them, the list goes on. None of this could have happened under US unipolarity.