No Aliens Didn't Come here for Gold. Here's Why

If I read this post right https://www.reddit.com/r/DaystromInstitute/comments/2xzfzc/comment/cp4wvs2/?utm_source=share&utm_medium=web2x&context=3 

Then the commentor estimated , if at max efficiency, " 7.45 x 10^14" Joules of energy would be needed to get 1KG of Gold.

As I understand it from a quick google, 430 Quintillion Joules of energy hits the earth every hour. That's  430*10^18. If we just round up the cost from that redis post to 10^18 because why not, then we have enough energy, hitting the planet every hour, to make 430 KG of gold. As I understand it that is, (430/1000) Tons every hour or 0.47 Tons of Gold produced per hour. There are 2,080 hours per year so 4,425 tons of gold could be produced annually with a solar capture surface area, equal to that of our planet, pointed at the Sun. 

As I understand it there are 244,040 tons of gold that will ever be available for use on earth ( accessible with current tech ?)  and we've mined  190,040 tones of it as of 2017. 

At a rate of 4,425 tons per year, it would take us 55 years to synthesize an amount of gold equivalent to all the gold that is easily accessible in the earth. 

Meaning, if an advanced civilization, can compose a small circular Dyson swarm, equal in diameter to the earth, they could synthesize more gold, than we have available in the earth, in the time it took them to make a one way trip to get here. 

That's assuming they can't get any efficiency benefit with gravity /spacetime bending tech.