You should have received an email with the reason, specifically the name that was selected for your WoW: Forever beta character. The email that I show that was sent includes the name. Check your spam filter/junk folder.
Character names must adhere to our naming policies, including in Beta. If you violate those policies that may result in the removal of beta access.
It isn’t a matter of “tuning”, we know what bad names are and we know people create characters with them all the time. We have a reporting option specifically to have those addressed. Some slip through the cracks here and there because they go unreported.
Having the option for a first/last name provides opportunities for a lot of… creativity, but our policies are still in place. The names themselves should continue to abide by our naming policies. The Development team for WoW: Forever is trying to address those names that are brought to their attention.
Beta is primarily run by QA and the Game Development team, so policy enforcement there primarily falls under their banner. However, if you feel an error was made you’ll want to submit an appeal. None of the examples I have seen thus far seem to be appropriate, but that isn’t my call.