I have not seen any widespread issues, there are always one-off devices that act dumb which is why I roll out major OS updates in waves. Granted we also upgraded the fleet to macOS 15 in December and January. 

What are your OS install logs and system logs saying?

Can you ssh into the device and kill the login window? I'm curious to see what happens? It might provide an answer to what's causing the issue. I would also tail the logs as well to get more insights.

forgive me @Wakko 

how would i ssh into the device what would be steps 
would that be through the terminal?

Sure thing, first get the iP of the device, then have your admin account [or management] info readily available.
You will need this to be able to ssh into the device.

In terminal use this to log in. When prompted then enter your password. Once enter you'll be console into the device in question. If ssh is not enabled you can use a policy to enable it on the device in question.

ssh xxx.XXX.xxx.XXX -l username

I managed to ssh into some of the effected devices and kill the login window it didnt turn provide any error message. It also appears to effect local login on some devices