How can I enable chat with everyone in Roblox?
Solution 1:
I found this on the Roblox site. If your account date of birth is set so that you are 12 years old or less you can only set the chat option to friends or no one.
Players age 12 and younger can select either Friends or No one, while players age 13 and older have additional options on who can interact with them.
Link: https://en.help.roblox.com/hc/en-us/articles/203313120-Safety-Features-Chat-Privacy-Filtering