I think you've got this whole thing backwards.
Atheism isn't based on evidence. It's based on lack of evidence. It's the non-atheists who have the burden of proof.
Noöne was indoctrinated into atheism. Atheism is the epistemic default. We're born non-believers. It's Religion that's learned.
I mean...one certainly COULD be indoctrinated into atheism. I spent some time considering how NOT to do that to my kids, for example.
Your point largely stands, but I think sometimes we (atheists) have trouble splitting what atheism is, and how atheists act.
Mind you, our theistic friends also commonly have trouble with this.