This a really good and intersting take.
To take this a step further, replicators can't make everything but can make most things. "Latinum" may be of value because it is truely a rare and cannot be faked - so gold pressed latinum becomes a currency because the Ferengi have faith in it's value as a fiat currency. It could also be that the method of gold pressing the latinum makes it near impossible to reproduce and fake, or that the latinum (some kind of alloy?) can only persist and be "stable" when it is pressed.
Superb episode, a real high mark. The 1st episode was so disappointing I was worried they'd gone of the rails with the nonsense kung fu segment in the middle, but Ad Astra Per Aspera was a perfect episode.
The writing was great, and the pace and rhythm perfect with highs and lows, good use of emotions and a perfect ending. I love these character driven episodes - we learnt more about Una, and also La'an in effective way, but also about the context and imperfections of the Federation. The cast is also great, making the close family like dynamics of the Enterprise command staff feel real.
I'm glad they also didn't put Pike on the stand. It allowed Una and Neera to shine, and Neera (Yetide Badaki) who was a superbly crafted and acted character - she ran the gauntlet of dislikeable to a most loved character in one episode.