As reported by 9to5Mac, Apple had made a change in macOS Big Sur that allowed Apple’s own apps to bypass firewall filters. This move raised concerns among developers and, in the macOS Big Sur 11.2 beta, Apple has responded and removed these apps from the exception list.
After some macOS apps…
Link: macOS Big Sur 11.2 beta 2 allows Apple’s apps to be blocked by firewalls
via http://www.imore.com