For n=1, at least, I appreciated the summary (even though I understand what you meant about spoiling it).

I habitually avoid videos on the internet, and with the summary, I was able to at least get the gist of the video, whereas otherwise, I would have never watched it.

Yes, because I think it is more useful to just write about the details of the potential "life-or-death situation" instead of linking to a long video about it. Your original comment was very clickbait-like, "What you don't know about hauntings could kill you!" If the whole thing can be spoiled with a short summary of the first couple of minutes, it's probably not worth watching anyway.

Edit: I have now added a spoiler warning to my original comment (I hadn't thought about this possibility, sorry)

It's okay to spoil something when the information might keep people from dying.