Are my rights being violated?

I am 22 years old, Ive worked EMS for 4 years now and I currently live with my parents while funneling what revenue i can towards college. To that end my parents allow me to remain on their phone plan.

The phone plan has an excessively strict web guard that prevents access to any forum, networking, job searching, gaming, social, browser access to YouTube, etc. Sites that can be researched are limited to email and mobile version of YouTube. The web guard is through T-Mobile and is intended for users under 18. When I asked why I couldnt access sites such as Barnes and Nobles and Books a Million I was told they were not going to negotiate restrictions or come down on their morals.

To be clear, I am not someone who has malicious intent and if I did I probably would be smart enough to get my own plan.

I do feel that they would try to prevent me from getting my own phone plan which is where the question comes in. How much control does a parent have over their childs life at this age? I am not intending this to sound rebellious or whiney but when I cant even make a linkedin page for career advancement because its supposedly immoral I cant help but feel like Im being wronged here.

I do not wish to disrespect or dishonor my parents in any way and i am truly grateful for the help that they provide. Any advice is apreciated.

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