We first became powerful because we did the industrial revolution before anyone else, and used more of that capacity to fight the world (and win) than to fight each other.

When we fought each other, after the industrial revolution, that was the Napoleonic Wars and the two World Wars.

> and ever since the creation of the EU it's been becoming less and less important on the world stage.

I wouldn't say it was "ever since the creation of the EU", but rather "roughly between WW1 and decolonisation". Post-Cold-War the EU has taken over from the former global importance of the member states, e.g. https://en.wikipedia.org/wiki/Brussels_effect

That said, east and South Asia are regaining their multi-millennia history of being the world's dominant power by virtue of having roughly half the total world population.

And to agree up-thread, there's plenty going that can rapidly turn the EU's economy into a disaster if not handled expertly.