Your strange and desperate attempts to turn this off-topic continue to be recognized, but for those still reading in good faith, it was resource allocation that was said to be the social construct. Who can afford and who cannot afford something is decided by the whims of people and nothing more.
Scarcity is a physical phenomenon. Only one $thing exists and more than one person wants it. Scarcity. The agreement to transfer that $thing to someone is based on humans respecting made up rules. Society. Social constructions. How we define affordability is different. You can "pay" in different ways, some that don't have physical mapping t real world like "social standing."
The laws of supply and demand and scarcity still apply, yes. But how that plays out is social. People have to agree or fight. "Affordability" is based on what we agree is worth an exchange. You may value the approval of the recipient more than money. What does affordability mean here? To curry favor later with someone else or because your moral framework lets you sleep better (they were a hungry kid and you don't want kids hungry - another kind of scarcity where we define affordability by how hungry you are).
Like you said, unless we redefine words. Then you can have affordability and scarcity mean the same thing.
Edit: snark reduction
I'm on board with people getting excited about living in a society, it is all pretty magical. But affordability isn't some random social construct, it is in great part about physical limits. Unless you want to redefine what words mean which is always an option available to us.