The problem is that meaning is undefined and this leads you down a rabbit hole of trying to figure out what is the meaning of life, which will make you very disappointed and lead to constructing a psychological bubble of "beliefs" that you appoint as facts to find a way out of this burdensome brooding.
Not everyone wants to live a lie like that, and have that sort of pseudo religious lifestyle. It's much easier to just go for the highest paying job, then making sure to also do some good (if you feel like it's too "evil"), by for example donating some of your salary, or doing some volunteer work. Why is this better? Because it's clear practical actionable goals that you can rely on, and that you know will have the desired outcome.
But it's more work to do this, assigning some superficial "meaning" to your job that you demand of all people around to validate and support, it's a way to be more lazy, to turn your social circle into a mini-cult where you all tell each other that you really can have the cake and eat it too.