This is basically a reason why it is always better to meet people in person. Well, you know what I mean people that you meet say at school, work, church and so on...
Yeah. Because people you meet in real life are much more reliable...
The issue isn't where you meet them but having the common sense to recognize when something's wrong.
Yet many scammers actually purposefully leave red flags, such as poor spelling and grammar, because they know if someone ignores it or misses it they have them hooked for sure.
Let's not forget BTK, John Wayne Gacy and Ted Bundy all were married, long before the internet.
Before the internet there were phone and even snail mail scams. Phone scams are still going on too.
I've met numerous people in person that I first met online. Never had a problem. I've never fallen for a scam. And someone tried catfishing me once but I knew something was wrong right away.