That wasn't a platitude. That was a suggestion that the smart place to end the conversation was there. If you'd like to continue it, we can, it's just not easy over text.
Poor people seem perfectly capable of purchasing car insurance, as evidenced by the fact that millions of poor people have car insurance. What is it, specifically, about being poor that leads you to believe they lack the cognitive ability to purchase disability insurance? Or did you understand something other than cognitive ability when you read they couldn't attain "expertise?"