Problems with macOS Ventura 13.3.1 and Safari 16.4

(2019 MBP, 16") Since updating to macOS Ventura 13.3.1 (April 2023) I have been unable to hide usernames from the Login or Lock screens. I have toggled the feature on and off, but the user names and AppleID icon are displayed no matter what. Not the worst thing in the world, but I would prefer to keep the usernames hidden.

Additionally, I am unable to use Safari to log into Google/Gmail. This problem presented itself when the Mail app asked me to reauthenticate two gmail accounts. This process opens a Safari browser window. Using Safari, or the Safari window that pops up from the Mail app, I am unable to get past the "Enter email" screen. I get the following error after entering my email address and before being asked for a password:

There was an error during the transport or processing of this request. Error code = 103, Path = /v3/signin/_/AccountsSignInUi/data/batchexecute

Notably, I am able to login to Google/Gmail using Firefox, Brave, and Chrome... The problem only persists in Safari. Safari is using default settings and no extensions - Version 16.4 (18615.1.26.11.22)

I'm open to suggestions. Thanks.