Prices is not something that is purely proportionnal. One thing might be cheap when you want only a small amount, but very expensive if you want a lot of it. This happens when you request more than what production can offer.
i know that if i want to buy all copper in word, near the end of my search it would be rarer than gold and cost more, but that is not exactly relevant is it?
now, tell me who will do all those simple and dull jobs when one won't have to?
who will be mining everyday for 30 years or staying month after month on oil platforms if they can do nothing or anything?
One word: machines.
well, we nowhere near that, are we?
besides - i really don't think that developing machines (self sustainable, completely universal - that would require proper AI) and letting everyone to do what they WANT to do and nothing else is such a great idea
and more, nowadays one can do whatever he wants, yet we still have plenty of some rebellious bullshit, why future supposed to be so much better?
Gold will probably never ever be free. However, one gram of gold will probably get more and more purchasing power, just because stuffs will be easier and easier to produce with time.
gram of gold was $5 in 1975 it is $45 now
first - almost half of price difference is inflation (whatever cost $5 in 1975 would cost $20 now)
so it is partially true, but consider one thing - products are more complex every day, they live shorter and are replaced by 'better' and dearer ones every single day
and what is more important, number of things on household is growing every day
you can get tons and tons of things you would use once or never, so even if today fridge is half the price when you add all 'necessary' things like displaying of current temp, automatically making ice cubes, auto defrosting, deep freezing, etc. etc. you end up spending same or more money for product that won't last 5 years while back then it would last 10-15 years without problems
family story: my grand grand mother bought light bulb back in 1935 (europe, gremany) and it last for 67 years - someone broke it during cleaning in 2002, today you are lucky when you get 67 days of light... producer will sell it 50 times cheaper today but it last 200 times shorter, even if they can make it last hundred years for few extra cents they won't...
we could get more better things over the time, but that is not going to happen... not only producers and marketing fault - people wants it because all those adverts, other people etc.
i used my first watch back in 1980's for more than 10 years, now i'm changing a sophisticated mobile, pc almost every couple years... partially because of new features, partially because it cost less to get new laptop than fix mobo in 5 years old...
i could get 5 or maybe 10 better watches for the money my dad paid back 1980, but who uses a watch this days? an cell phone (which costs the same) is todays watch