I've noticed this too and I agree it's unacceptable practice. Journalism in general has become wildly resistant to properly citing their sources (or they simply make their citation as difficult to find as possible through various obfuscation techniques) and this is making independent validation of any information online that much more difficult while further entrenching a culture of "just trust me, bro" on the internet in general. It's a deeply infuriating and destructive practice that needs to die out. At least when I was in school & university, properly citing your sources was everything when it came to writing any sort of report or essay. How the adtech industry managed to quietly undo that standard expectation so thoroughly for the sake of engagement metrics is rather nuts to me.