I appreciate your statement:
“because who you are underneath it all is who everything outside of you is underneath.”
The idea that we are founded in and originated from a transcendental source is a fundamental concept for understanding the Neterian teachings. Yet most are not able or ready to hear such a magnanimous statement and then accept the awesome implications it portends.
About your other point, indeed, the concept of a devil as a kind of religious excuse for bad behavior and vile feelings that supports egoism and the society that is founded in and dependent on believing in egoism for its very survival. Can we imagine people not being able to hold on to the idea that Obama, the Kardashians, or Hollywood stars are happy and they are good and mean well for all and aspiring to be like them, one of them some day? Can we imagine people not being able to hold on to the idea that the USA is a good country even though it massacred the original inhabitants and enslaved whole populations and still without apologizing or reparations? Can we imagine people not being able to hold on to the idea that driving cars and polluting everywhere to facilitate comfort and Black Friday?
Those who are evolving can understand and accept the fallacy of such false dependencies and move forward on their spiritual journey without devils and without false hope, by relying on truth (Maat).