What you are most likely facing with your parents is an unconscious fear of destabilizing change … it’s an evolved, built-in program I call “homeostasis preservation”.
I’d have to better understand your parents personality & defenses to know how they would deny & deflect my arguments. As such, I don’t know that I can give you a clean & guaranteed way to succeed.
I’ve not seen anyone be able to mount credible arguments to this position, but since your parents are in charge, I wouldn’t assume they will hold themselves to credible & reasonable standards. They may block you just because they don’t want a light shone upon their patterns & the family dynamics—aka homeostasis preservation.
Dewey Gaedcke’s answer to What are the benefits of seeking therapy?