I like what Russ Harlan said earlier in the comments: living and klicking in the feedback bubble means little to no actual reading, zero critical thinking — it's just the feels. This is something that is enabled by two factors in my opinion.

The most important influence is how we are raised by our parents which reflects in ones individual ambiguity tolerance, which means ability to cope with disagreement. If you are used to a fair culture in your family to express your thoughts and overcome prejudice, then you withstand probably the urge to just react only to outside triggers.

The second part is how software is designed to support critical thinking and communication. First thing that came to mind is how late in the 2000s I understood the beauty of pingbacks on blogs, not exactly the best example of low-threshold access that social networks establish today. Manton Reece has a micro blog service in the making for quite a time. Last week he wrote on his blog:

"It’s not easy to build software that encourages good behavior. When I look at my Instagram timeline I see beautiful photos, hand-drawn art, and snapshots of everyday life. I see the very best of the world. It’s not the full truth, but it’s all true.

Instagram was no accident. The only question: was it unique to photos, or can the same quality be applied to microblogging?"

http://www.manton.org/2016/11/fake-news-and-instagram.html

I look very forward to the ongoing process how we take over responsibility to shape fair & critical ways to communicate.