We will never be post scarcity without fundamentally altering human nature.
If an AI singularity happened and a dyson sphere was put around the sun and the seeds of humanity had spread to a hundred thousand stars, then there would still be scarcity, it might not be material but it would still exist (in the form of limited processing power mainly).
Even if there is a radical redefinition of what can be produced and what you need to buy, there will still be scarcity. Raw materials, electricity, land and processing power will never become unlimited, yes they can get to a point where they become so hugely available that anyone could own a mansion and a hyper-intelligent AI and run their own power plant, but they would still be limited.
For instance, I don't think that current computers (and probably not even most computer parts) will ever really be printed by non-industrial 3D printers, because A) They are crazy complicated, and by the time non-industrial printing catches up to where they are now, they will be much farther ahead, although if you want to print a few decades out of date tech you would probably be able to do it and B) usually the cost for them isn't much higher then the cost it took to make them (compared to other things at least where brand and market power make them many many times more expensive). Printing them yourself would probably (if at all possible) cost more then twice as much and take more then 10 times as long, when you can just drive to the store and get it better, cheaper and faster I don't see anyone but huge nerds making computer parts