Does it have something to do with the rise of smartphones and no one typing on real keyboards? (Maybe why blogs died.)
Is it a consequence of voting, which blogs didn’t have?
What happens to your thoughts? Do you turn them all in the form of a question? Do you tear them down into a Mastodon one-liner and hope a popular person notices it?
If Lemmy had more of ourselves in this way, maybe it would be a healthier place.
Being idle until the media put out an article on something for us to talk about gives them too much power over us.
There’s an actual_discussion community, which isn’t exactly lively. There’s a casualconversation community, and even that’s all in the form of a question.
Of course that depends where you read and post on Lemmy. I don’t really agree with the premise of your question, so I can’t give you a good answer except to say look around. Depending on the topic, you can find people who are going into great detail about their own thoughts and presenting arguments and facts and whatnot, all as might be appropriate to the topic at hand. I’m not really sure what you’re looking for. It sounds like maybe you want to start a blog, and if you want to start a blog, go start one. You can even post the links here, for an extra touch of irony.
Start a blog is a little like “If you don’t like the huge corporation, you have to start your own huge corporation to crush them”. Make a blog, never be seen again.
As for people giving their thoughts, it seems held back until you free it with a link or a question.