Yep. ABC is less digitized and hides most full broadcast programs from the public (gotta be an employee for that). But https://www.abcnewsvsource.com/ is the Silverlight run site with everything. Someone should probably archive everything incase the Silverlight shutdown this year kills the site. Ripping it is mildly easy.
PBS/WGBH stores everything at https://americanarchive.org/ which for copyright reasons, some stuff can only be viewed at the LOC or WGBH. The physical only content includes a number of interesting items though like the few Mr. Rogers episodes not aired on Twitch, or around 2000 non-public but aired Sesame Street episodes.
Archive Team already has some private archives of news stuff that I assume they'd like to add to. They have rips of every nightly news broadcast from 1969 till 2018 which they'll probably never release. Would love to help them though.
(Anyway, thanks for doing it!)