That graphic is wrong.
France, Spain and Portugal never really was world reserve currency. Italian money was (Florines, Ducats), from Florence and Venice respectively, before the Dutch rule of trade and their Gulden.
Spain and Portugal was only important for the Latin American trade, gathering silver and gold to send to the Far East. France may have had a short period of currency dominance during Napoleon.
I don't think they are going for accuracy, they couldn't even get the UK flag right even during that period of time it didn't look like that 🤦♂️
What's interesting is that fiat currency has failed for both USA and UK.
Pure silver pound was temporarily suspended, mixing in less precious metals, resulting in failure and inflation. I believe the UK returned to pure silver as a consequence.
I don't know how long the pure silver dollar reigned, after that I guess came a period of gold backing until pure fiat was introduced.
Florines, ducats and gulden became famous and valuable currency for their high gold content, I believe 3,5 grams of pure gold.
