Yes, in tackling knife crime in my area they do teach people how to try and avoid things too. Like not associating with gangs, speaking up if you're being threatened etc. I have seen lots of police forces have schemes or linked charities set up to reach those people and try to tell them how to avoid a certain lifestyle that would make being stabbed more likely.
So if we tell children, do not accept sweets from a stranger and do not get into their cars there are bad people who want to do bad things to you, why isn't that victim blaming. The price they'd pay is being kidnapped and worse, and they know this.
Lots of people do make risky decisions and would do everything that the tweet said, they would go to house parties with people they don't know and they would get drunk with a bunch of strangers, so yes some do need to be told over and over that this is risky and to avoid it.
I know I made really dumb decisions at times when I was younger, so did lots of my friends, we look back now and know we were being very naive. Lots of people do. We can't pretend that accepting lifts etc from strangers is suddenly OK now they're not children. We send the message to them throughout childhood, why suddenly stop it in adulthood?