That 1873 swindle was temporary. The money supply had to be expanded. The silver boom was on, the next gold rush was unknown, 25 years away. In 1878 silver dollars started coming in a flood, and they were legal tender with no limit. The Carson City mint had been established in 1870. In 1871 the copper and nickel coinages were made fully legal tender with no limit.
This looking back and calling silver tokens as if it was a given to be permanently of lesser value is granting decades of hindsight to the participants. The point of "demonetizing" silver was to PROTECT both metals from speculative melting. Thereby allowing BOTH to remain in the money supply. In the event, it was the silver price that initially fell (after 1870), precisely because of that silver boom. Comes 1920 and it went the other way. Not enough to drive it out in the US, and the price fell back down in the 1930's.
The driver to all this was merely the desire to have one single money unit. The US screwed up in 1792, trying to be too progressive with too little experience. The real and escudo went blithely on as before. In Britain it was the desire to not have to separately account for guineas and pounds sterling.
So regarding the original premise that the royal mint could have issued tin crowns, shillings and sixpences, but because they promised to give out gold for them they ought to have been, in 1816, accepted: How would people be "educated" to KNOW the future? That catastrophe, failure, over production or swindle, could not make tin coins worthless by 1821? Exactly at that time much paper money in the US had become worthless, and specie payment WAS suspended in the 1830's. And 1860's. And famously in 1935.
Britain used the patriotic cover of the World War to stop redeeming anything in gold. It was the 100 year past "education" which put that over. In the US the calling of gold was the realization of the worst nightmare predictions of 100% gold upholders, YET, because of seizing both an opportunity, and a catastrophe, there was no inflation immediately, and a very small amount for many decades.
The "education" that I got, personally, circa 1965-1985 is that money is an ephemera, liable at any time to plunge in value. Or rather, have its value appropriated by its very guarantor. But I must use that paper which I don't like.