They’re email lists. Or just lists.
Some of those lists use the Listserv® software from L-Soft.
Many others different list software from other companies.
It’s sort of like there being librarians (or professional librarians) and others who happen to work in libraries.
And, y’know, librarians really should be able to make the distinction.
Heck, at home we use Safeway Home (previously Softly) facial tissues rather than Kleenex® tissues. Because we like them better.