What analogy exactly?
This seems to be a case of people saying “this statement is false because there is a way to interpret the sentence that makes it false.”
When it starts "the same kind of ", that’s when you know it’s an analogy.
No, no one is actually indirectly saying that. But lots of time spent writing is, aside from some super-rare prodigies, necessary to produce quality output. Successful authors spend a lot of time coming up with ideas, writing and revising stories, writing and ditching stories, reading other people’s stories to get new ideas for both structure and content. Also being wealthy provides more opportunity to network with other wealthy people to get a recommendation that a poor person not moving in those social circles would lack. And means that one can keep trying new writing and submitting it until someone decides to publish it without having to balance writing with ‘how many hours do I work to keep the power on this month’.
And I’m not aware of any authors who’s output worsened when their material success freed them to be full-time writers - the pattern I’ve always seen is that their output actually worsened when they got enough clout that their material wasn’t being edited or outright rejected. It’s the lack of editorial oversight that led to them writing junk, not the lack of needing to work non-writing jobs to eat.