"Unable to initialize connection to Steam. Please Ensure the game was launched through Stream or try again later."

My Steam is online, I literally pressed play from in the Steam UI.

I tried open ports as recommended here: https://help.elderscrollsonline.com/app/answers/detail/a_id/1133/~/what-ports-do-i-need-to-open-for-the-elder-scrolls-online%3F

Port configuration in my router: 433,4380,24100-24131,24300-24331,24500-24507,27000-27050

Same error. This is my 5th attempt to log in over the span of a week, so "try again later" isn't the issue either.