She's almost 70, spend all day watching q-anon style of videos (but in Spanish) and every day she's anguished about something new, last week was asking us to start digging a nuclear shelter because Russia was dropped a nuclear bomb over Ukraine. Before that she was begging us to install reinforced doors because the indigenous population were about to invade the cities and kill everyone with poisonous arrows. I have access to her YouTube account and I'm trying to unsubscribe and report the videos, but the reccomended videos keep feeding her more crazy shit.
The videos you watch on Youtube influence the ones you're recommended. I once put in a couple of 8 hour cat videos for to entertain a feline friend while I was away, and for a while Youtube kept recommending them to me. I had convinced it that I was a cat.
Get her to watch other videos (or even watch them on her behalf using her account), and also mark the awful ones at Not Interested > I Don't Like This Video using the thumbnail menu. It'll take some concerted effort though.
Also, even if you manage to get the recommendations out off of her front page generally, if one shows up and she clicks on it, it'll start recommending them again. Youtube's recommendation algorithm is really crappy, and assume you're all about the things you watch recently.