It is in fact 110% illegal friend.
https://www.theverge.com/2015/10/27/9622560/jailbreak-video-game-console-sony-microsoft-dmca
"The exemptions are important because they allow consumers to install third-party software, in other words jailbreak, most of those gadgets without risking copyright infringement. The reason game consoles were left out is because a jailbroken one would primarily be used for playing stolen games, says the Electronic Software Association, the game industry's largest trade group and the main opposition to the exemption. The Library of Congress order reads:"
Not only did they keep it illegal as that says, there is pages upon pages of added legislature in the docket that makes it more illegal than it was. I dont know where you get that its legal, it isnt. Game Consoles and Ebooks and a few other purpose devices with strong piracy concerns are extremely illegal to modify as of the 2015 ruling that made everything else okay.