I have a new 15" MacBook Pro running Big Sur. Many things changed, one of them being that messages from unknown senders won't appear on my laptop Messages. They arrive on my iOS devices.
A previous response to a similar question was not useful.
MacBook Pro 15″, macOS 11.0
Greetings, PL00!
Thanks for reaching out to the Apple Support Communities! It sounds like you're not seeing messages from unknown senders on your Mac. Let's start by opening Messages. Then go to the menu bar > Messages > Preferences and turn on the option to get notifications of messages from unknown senders. Then, see if you're seeing the messages when they come in.
If you still have any issue, we recommend taking a look at this article with steps to follow for How to use safe mode on your Mac. This will perform checks and stop certain software from starting up automatically. Once you are in safe mode, test to see if you have the same issue.
Let us know the results and have a terrific day!
Messages from unknown senders not appearing in Messages on my MacBook Pro
