Can you purchase uranium?
No.
I absolutely can. Perhaps not legally and perhaps not cheaply, but yes, I absolutely can.
Can you buy gold, aluminum, silver, etc.?
Yes.
It's modeled on real life. There are some things you simply can't buy.
Aside from happiness, name one.
Manufactured materials you can't buy because they're specially manufactured. You can't go out and buy the parts to build an F22 Raptor. You can buy all the elements and circuits to build it if you can figure out how to engineer it all yourself, but not the actual parts.
Again, the game is modeled on real life.
It's funny that you specifically mention the F22. A good personal friend of mine worked on its development and again, you are wrong. Given a lack of morality and plenty of access to cash, things can be bought. You might perceive that there are barriers to that - and you are correct in that there are - but everything has a price for someone.
All that aside...the fact that I can't purchase phosphorus but can freely hoover it up is just silly. I get it, FDev wants you to go through the game loops, fine. But after a certain point, we should be able to skip the line. It's just forced engagement to boost time in game numbers for share holders , pure and simple.