I don't know much about this subject, but I see you have no replies yet so I'll give you my guess based on reading others' posts...
I think you might have an MDM Profile installed on the Mac. These are usually installed by a business or a school to set up the machine and enforce corporate or school policies. It may prevent you from being able to change certain settings.
Did you get the Mac from your employer or school? If so my guess is probably right and you should ask them about the flashing text. I haven't seen any other posts about flashing text like that so I don't think it's a standard thing, even with a Profile installed.
On Monterey I think you can see if an MDM Profile is installed by going to System Preferences-->Network-->(Ethernet or WiFi)-->802.1X. In Ventura's new System Settings things may be rearranged, so I'm not exactly sure where to find it in Ventura, sorry.