Yes, it still works.
Why? Content is still expensive. You have to understand that unless you’re talking about blogs that are specifically set up for guest posts, people are going to still read organic and real content.
The old game of exchanging a link for on-point, high-quality content is still going on. I don’t think it will ever go out of style because no matter how successful a blog is, it’ll never reach a point where it has so much money that it doesn’t have to worry about content costs.
Also, it helps tremendously if you are an expert in your niche and you use guest posting to build a name for yourself.
If you want a more effective and efficient guest posting strategy, start investing in becoming an expert and as more people see your guest posts, the more likely they will publish them.
In many cases, you don’t even have to email them because they will come after you. So focus on the value that you can give to others and everything else will fall into place.