Pornography is protected under the first amendment, and sharing it via the internet is allowed. Child pornography is illegal and should stay illegal. Similarly there are other forms of speech that are criminal and should stay criminal, such as death threats. I think you would agree that these are reasonable regulations on our free speech.
Here’s an example on the gun side: in the 2017 Las Vegas mass shooting, bump stocks were used, allowing one man to kill 60 people and injure an additional 867 (just to confirm this is not a typo: 927 people were killed or harmed). Bump stocks were banned in 2018. The bump stock ban seems justified to me, does it seem justified to you?