Imagine that you are in a field filled with imposters. 

• Perhaps you are a doctor or nurse who truly cares about the wellbeing of your patients, and you're in a mismanaged hospital where most doctors do little to no good at all. 
• Perhaps you are a passionate software engineer in a company filled with ladder-climbers who care more about hacking the promotion structure than delivering a good product.
• Perhaps you are a teacher who goes the extra mile to help all of your children learn, while your colleagues are busy goodhart-ing a small set of test scores.

If your field is useful, then you can do quite a lot of good by staying in your field and not becoming an imposter.

It costs the hospital/company/school the same amount of money to hire you as it costs them to hire someone else. However, by virtue of your lack of Goodharting, you are able to do more good than another employee with your pay. 

When considering whether to do direct work or earn to give, it might be worth considering whether you're likely to be an imposter. If you wouldn't be an imposter, then you might just be worth much more than the next employee.