Are IRL friendships healthy?
There's no difference in my opinion. Sure you're separated by a screen, but it doesn't stop you from being able to get to know a person. People can lie in real life, just the same as people can on the internet. It's a little different in manner of communication and things, but overall I don't see how it can be considered "unhealthy" whereas IRL friends can be considered "healthy." If your IRL friends are convincing you to commit crimes whilst your internet friends are telling you not to, which friends are the unhealthy ones? Separation by distance doesn't determine the quality of friends.
The vast majority of the cases where people have met up with someone they met on facebook or something, and it turned out to be a pedo, the victim is essentially a "noob". They have no idea what they are doing, they more than likely haven't known the person that long or developed a true friendship. I personally find someone's intentions pretty obvious and I'm not going to make an internet friendship with the sort of person that spends their spare time on Omegle asking for "asl?" There are some cases where people can portray a convincing false persona, but it's only a very small minority. If people know what they're doing then they won't fall victim to such cases. Yes there are people who fall victim to crazy internet stalkers, but the same thing happens in reality and we don't say it's unhealthy to leave your house in case there's a murderer or rapist waiting around the corner.
I don't form friendships well in real life, because my options are limited and it's hard for me to find people I can really get along with. In reality, I only ever really meet people in the same classes as me. Sure I like to hang around with them sometimes, but I haven't ever developed the sort of friendship I have with my online friends, just because I simply don't like the people I know in real life as much as the people I have managed to meet online. I can truly be myself with them because they're decent people. On the internet, you can be connected with millions of people from all across the planet. In reality, it's much more difficult to find people. I even have difficulty finding people I can truly be friends with when I am on the internet, I've never had any luck finding such people in reality.
It doesn't distract me from forming IRL friendships. I do have IRL friends, they just aren't the sort of people I could ever really connect with. Even if I didn't have the internet, I wouldn't spend the free time looking for more IRL friends, I'd just waste it doing something else and spend even less time socialising, because I wouldn't have any 'decent' friends at all. That would be "unhealthy" so in a sense the internet has actually improved my life.
