Birthright. Parents, grandparents, etc. fought for their wealth, freedoms, rights, etc.
You can’t own progress, you can’t own a society, and you definitely can’t own the concept of freedom (can’t believe that isn’t clear).
Your ancestors were thieves and oppressors, and took things that didn’t belong to them, which means the resulting better society isn’t yours or theirs to give or take. It’s free for whoever comes and helps grow it.
Honestly I wish we had some mechanism to cast out the entitled and let in the hopeful. People who believe as you do don’t deserve the gift of a progressive society.
You are a self-loathing, little person.
I personally think their statement has a high likelihood of being valid, at least in part, and only on a probabilistic basis.
Your response indicates they hit a nerve.