You could suggest that it's still scarcity, but defining scarcity on an individual or even local level is a bit strange given the fairly globally connected world we live in.
You mean... a scarcity which is not natural? Artificial scarcity?
People are poor because other people can be, and want to be, rich, at the expense of other people if necessary.
There will never be any such thing as a "post scarcity" economy until humans stop being humans.
So, in your world wealth is finite and if I have more then by definition it is because I, directly or indirectly, took it from someone that has less? What a dreary and depressing little world you live in.
Out here in the real world wealth is created by the process of work and innovation among other things. Wealth is not this finite pool where if I have more then you have less.
There will never be a post scarcity economy until we figure out a way for virtually limitless energy. Not very cheap, but limitless and the ways to use it to directly provide goods. That is what makes the Federation run and allows people to work more or less only when they want to. The combination of replicators and limitless energy, which at this point may as well be magic. Coincidentally magic is pretty much required to make any socialist utopia run for too long so I guess one ought not be surprised.
One thing that is never answered in the ST universe is why would anyone want to be a waiter in a restaurant (or similar service job)? They show them from time to time but the number of people who feel their true calling in life is to bring people food and deal with crappy attitudes is vanishingly small so where do they come from?