Militarily, economically, or politically? Because either way, I disagree that things are shifting away from US domination.
Militarily, it's really no contest. The US has no major threats to its air superiority, leads the world in managing military logistics, has military bases around the world, has combat experience, a flexible command structure, and is far ahead of its near-peers not only in military technology, but the necessary training to use it. The best example of this is looking at our closest rival, Russia, and how it's managing the war in Ukraine. They are struggling to maintain air superiority, completely fucked logistically, running clunky, inflexible operations, and seemingly lack GPS, optics, NODs, effective precision-guided munitions (theirs are seemingly much less effective than the US'), and drone support.
Economically, I have to admit I'm really not an expert on the matter. China seems to be a strong rival economically, and there's some talk in the Middle East about hedging their bets on China over the US; though from what I understand China's economy is a house of cards and seems to be slowing down. Either way though, the US still has enough economic weight to not really have to worry about its influence completely collapsing (I don't think).
Politically, most of what's going on seems to be strengthening the US' power. Russia's bullshit in Ukraine basically scared every Eastern European country not already part of NATO (or run by a Russian puppet) to start considering NATO membership. China's bullshit in general has basically scared all of it's neighbors into a closer relationship with each other and the US against China. I think the one place we're starting to lose some political footing in is the Middle East, though we still have a good relationship with the main military and economic powerhouses there.
I wouldn't be surprised if the world lets them have Taiwan back
Given that Taiwan is responsible for something like 98% of the world's semiconductor production and most of the world hates China, I doubt we'd just let China take Taiwan. Also, I think a lot of China's neighbors have a defense pact with Taiwan. They at the very least have a vested interest in not seeing the CCP grow any stronger.
Also, Taiwan is the remnants of pre-communist China, so it's not really the CCP's to take "back."