That's a rather smarmy response for someone who clearly lacks reading comprehension. I'd recommend:
(1) look up the definition of "disincentive". The parent didn't say anything about people not wanting to work or not wanting to be useful. And even then, you actually agreed about it being the disincentive ("if I support you but threaten to stop supporting you as soon as you get to work for money—suddenly working for money looks less attractive").
(2) understand the meaning of the phrase "The problem with X today is Y". It's very clearly not saying that Y is a problem with X, in fact, it's implying that there are other approaches to X that don't have problem Y.
(1) look up the definition of "disincentive". The parent didn't say anything about people not wanting to work or not wanting to be useful. And even then, you actually agreed about it being the disincentive ("if I support you but threaten to stop supporting you as soon as you get to work for money—suddenly working for money looks less attractive").
(2) understand the meaning of the phrase "The problem with X today is Y". It's very clearly not saying that Y is a problem with X, in fact, it's implying that there are other approaches to X that don't have problem Y.