"people who do not tag NSFW things such as graphic blow job or sex initial image and it shows up in everyone's feed"

Thanks, that a really good point - on my recent post about flagging not a single person came up with any good arguments like that for flagging!

The spam part is still a mystery because the whole of Steemit is full of spam comments, and they are not flagged. I think if people said flagging prevented porn rather that spam it would make a lot more sense.

This looks like an example of flagging not working:
https://steemit.com/steemit/@utfull/attention-steemit-spam-comments-are-now-getting-huge-upvotes

I remember when NSFW was first set up a bunch of people were freaking out, but although I've always had it set to show, I've barely ever encountered any!

I did post one myself once as a bit of a joke