Because everything about the last two hundred years has been explosive tech growth - and the countries who were players in 1800 are basically the same players today (plus the two startups Germany and Japan from 1860s) - they all just held on through steam, turbines, internal combustion and electrical.
What chnaged in those countries and cultures that was not driven by (at minimum) power generation methods?
Plus it may be an observation (I agree with) that companies eventually corrude and decline - but why? what is the mechanism - can we observe it? Chnage it?
Not really though. Portugal, Belgium and the Netherlands were major colonial powers in 1800 and are bit players today compared with how they were back then.
Plus Chinese historians will have you believe they've been the first civilization around for 5k years. (the truth is there has been rise and fall, but each subsequent one claims to be the _real_ dynasty and so continues from the beginning) so is China new or old?
I think the truth is geographical places rise and fall multiple times. They go through cycles both internally (need, growth, comfort, decay) and externally as their characteristics are useful/useless to the greater world around them.
Eg: I doubt China would have established its current power without inexpensive labor, telecommunications, and American debt fueled consumerism. Had China been a middle power in like 1900-1950 then another country might have absorbed the USA's consumer demand
What chnaged in those countries and cultures that was not driven by (at minimum) power generation methods?
Plus it may be an observation (I agree with) that companies eventually corrude and decline - but why? what is the mechanism - can we observe it? Chnage it?