My wife and I are currently rewatching season 4 of The Expanse on Amazon Prime before starting the brand-new season 5 (so we can remember the state of the plot threads that will continue -- the main story of Season 4, which is essentially a Western, ends, but the parallel stories happening elsewhere go on): serious space opera set in the 23rd century -- Earth and the Moon controlled by a one-world government grown from the United Nations (but with the Secretary General elected by popular vote), Mars colonized and independent (evidently after a war of independence), with a culture that feels American, even has a VA, albeit with freedoms restricted by the constraints of living entirely in cities carved into the rock (that give the feel of living in a shopping mall), and the Belt -- the asteroid belt and the moons of the outer planets -- as a lawless frontier where the prospectors have their own nuclear bombs for disassembling asteroids, hauling ice from comets to provide water for the larger colonized asteroids is a serious business, the locals speak an English based pidgin with African and Chinese words, and the nascent government is regarded as terrorists by the "Inners" as they call people from Earth, the Moon and Mars.
Well, that's how it starts. And it gets weirder and more complicated from there. It's predicated on our having managed to build high-yield fusion reactors and from them fusion drives for space ships, ignoring the dangers to fast moving space ships posed micro-meteors, and on our solar system having been visited by aliens, who aren't around any more, but left things behind. It's a rollicking good tale if you ignore the implausibilities (which are minuscule compared to the implausibilities of Star Trek).