Certainly charities exist that are ineffective, but there is very strong evidence that there exist charities that do enormous amounts of direct, targeted good.
givewell.org is probably the most prominent org recommended by many EAs that does and aggregates research on charitable interventions and shows with strong RCT evidence that a marginal charitable donation can save a life for between $3,000 and $5,500. This estimate has uncertainty, but there's extremely strong evidence that money to good charities like the ones GiveWell recommends massively improves people's lives.
GiveDirectly is another org that's much more straightforward - giving money directly to people in extreme poverty, with very low overheads. The evidence that that improves people's lives is very very strong (https://www.givedirectly.org/gdresearch/).
It absolutely makes sense to be concerned about "is my hypothetical charitable donation actually doing good", which is more or less a premise of the EA movement. But the answer seems to be "emphatically, yes, there are ways to donate money that do an enormous amount of good".
GiveWell actually benchmarks their charity recommendations against direct cash transfers and will generally only recommend charities whose benefits are Nx cash for some N that I don't remember off the top of my head. I buy that lots of charities aren't effective, but some are!
That said I also think that longer term research and investment in things like infrastructure matters too and can't easily be measured as an RCT. GiveWell style giving is great and it's awesome that the evidence is so strong (and it's most of my charitable giving), but that doesn't mean other charities with less easily researched goals are bad necessarily.
The Open Philanthropy Project is one major actor in EA that focuses mostly on "less easily researched goals" and riskier giving (but potentially higher-impact on average) than GiveWell.
Eventually, almost any organization distorts from its nominal goal to self-perpetuation.
As the numbers get larger, it becomes easier and easier to suggest that the organization's continued existence is still a net positive as you waste more and more on the organization bloating.
It's also surprisingly hard to avoid - consider how the ACA required that 85% of premiums go to care, and how that meant that the incentives became for the prices to become enormous.
How? I'm curious because the numbers are so specific ($5000 = 1 human life), unclouded by the usual variances of getting the money to people at a macro scale and having it go through many hands and across borders. Is it related to treating a specific illness that just objectively costs that much to treat?
A weird corollary to this is that if you work for one of these charities, you’re paid in human lives (say you make $50k, that’s ten people who could have been saved).
That's an extremely weird way to think about it. The same logic applies to anyone doing any job - whatever money you spend on yourself could be spent saving lives instead, if you really want to think about it that way. There's no reason that people working for an effective charity should feel more guilty about their salaries than people working for any other job - if anything it's the opposite, since salaries usually do not reflect the full value of a person's work.
No it isn't. EA folks do not think that people who work for charities specifically should be paid less or feel guiltier about their salaries (indeed witness the whole Scottish Castle drama, if anything it's the opposite).
The reasonable way to think of it is that if you were not paid those 50k, the chatity eould be less able to deliver on this. It would be amortized over the entire sum of people being helped by the charity, eventually becoming a negligible overhead.
This is sadly still true, given the percentage of money that goes to getting someone some help vs the amount dedicated to actually helping.