Twitter is not like random comments section, because you can build your own network of interesting people by following only what genuinely interests you. There are a lot of great people on Twitter working on products you or I use every day that share good commentary or tease what's coming, curate links that I'll probably be interested in reading or share a "heads up" if there's something to be vary of, reporters following a story, bands for upcoming plans etc. etc.
It's also interesting to follow some people you strongly disagree with just to see their day to day thinking, what they're reading and how they may've come to their conclusions.
You can also share a request/call into action/product you just launched etc. with your network and they'll spread it for you if you provide them with an interesting feed and generally quality stuff - must be a quality list of people you follow/they follow etc.
It's like your own personal humint if you know how to take advantage of it.
If you just engage with a bunch of random people, it's not that useful indeed.