I happened to be poking around in their issues to see if there were mirrors and observed that in addition to the linked status page on this thread, the underlying Eclipse Foundation has their own (multiple) status tracking channels

most relevant: https://www.eclipsestatus.io/incident/549796?mp=true

their helpdesk ticket: https://gitlab.eclipse.org/eclipsefdn/helpdesk/-/issues/5924...

the issue in their GitHub issue tracking for the site: https://github.com/EclipseFdn/open-vsx.org/issues/3805

the tl;dr seems to be a massive storage failure affecting a bunch of Eclipse services, and just like any storage problem putting all the bytes back is some "please wait"