Tbf I actually agree with you. Just messing around. I don't think China is gonna be the new global superpower any time soon, no. And I can't see any other major contenders right now. Unless it's a supranational bloc or something. Or some dramatic global event (like a major war or natural disaster) completely redraws the game board. Who knows if some completely new entity appears in the game that no one could've predicted.
But... US hegemony can't last forever. It will eventually end, like everything. The question is just when. Could be 100 years, could be 500. Could be 50. I think Trump might be speeding up that decline a bit though. Without US support, a lot of its allies in Europe and elsewhere are already regrouping and looking to strengthen ties elsewhere. There's a fair bit of talk about how the US under Trump is no longer the staunch reliable ally it once was and we'll need to reconsider our options slightly. In terms of economics, resources and even defence.
I expect Trump supporters are gonna vehemently disagree with me on that, and that more isolationist approach may be what they want anyway. But it's what I've seen being discussed.
As for the English language, I think that will probably remain the dominant global language even long after the political decline of the US, since it's become adopted as the main language of communication by so much of the world. (And I can't see Chinese (or rather its major dialects) taking over that role any time soon either, if ever.) Without the US though (or even with it) English could well morph into its own new thing as it establishes itself as the second language of much of the globe and second-language speakers end up vastly outnumbering native speakers. (I think that may already be the case.)
Then it will also one day fade away and be supplanted by another, but it's anyone's guess how long that will take. I don't think we'll be speaking English by the time we're at Star Trek level. (Or maybe we'll be speaking some future descendant of it, similar to how Latin evolved into Romance languages.)