While your concern is understandable, I don't think it's possible to outright disable username and skin reporting. Remember, Mojang already has access to all your data, including your username and skin as they host these files. Tools like NameMC can let anyone look it up as well.
Bypassing the in-game reporting system wouldn't really help as someone can still contact Mojang support, and they would be able to look up the name and skin histories for any given user.
Mojang has long been known for taking action against usernames they find inappropriate. Case in point, Marc_IRL famously renamed the user "MojangSucksDick" to "NoWeDont" all the way back in 2015.
Edit: It was Marc, not Jeb.