- Don't invest more than you can comfortably lose.
- Don't throw away the entire concept just because it's not perfect.
- Get better at telling who's full of shit, or delegate it to someone you trust.
#2: Just because there are charities or companies that do bad things, doesn't mean the concepts of charities and companies, or philanthropy and markets, are fundamentally broken. There are good and bad charities/companies, even though it may be hard to tell which is which.
#3: You can make your donations more effective if you get better at telling which charity is good (same for investments and companies). There are diminishing returns on effort here - particularly if you aren't planning to specialize in charity evaluation. In that case, you can convert this problem into an easier problem of finding trustworthy specialists in charity evaluation, and donating to places they consider good/effective.