Debian is an all-volunteer organisation. Those are the terms for participation and they apply equally to all. If you want to be paid for writing free software, then get a job with a company that does that. Debian is not a company.
So people who are wealthy enough to not have to worry about getting paid for their work have more merit than those who need to make rent?
This seems like a very Jane Austin-era view of meritocracy.
Debian contributors are volunteers. They volunteer their time, personal resources such as compute hardware, bandwidth etc. Some pay out of their pocket for running mirrors, compute resources and other infrastructure. Other parts are paid for by donations and infrastructure provision by sponsors. But far from all of it.
So at a personal level, individuals must be able to support themselves sufficiently to be able to contribute. That's no different from working in any other volunteer organisation which requires a commitment of free time and other resources to participate. That's life. Nothing comes totally for free. The bottom line is that participation at a minimum requires you to donate some of your free time. You're a volunteer, not an employee. What more do you really expect here?
In other words, I think this reply shifts the context from "will paying volunteers harm the project?" to "is paying volunteers morally right because it enables wider participation?"
Is it a meritocracy if only developers who can afford to work for free participates?