Apple released macOS Big Sur last week and while it had some issues getting to everyone and also causing some repercussions for other Apple services, Big Sur now seems to be bricking some older models of MacBook Pro, specially ones from late 2013 and mid 2014 for the 13-inch version. Some customers have had mixed results, with Apple saying there is a known issue and Engadget reached out to Apple which said at least one customer had to send their machine into Apple to be serviced.

Probably the best advice for now if you do have a late 2013 and mid 2014 13-inch MacBook Pro is to not update until further notice.