LinkedIn content is trash to be honest. If I were to put effort into a good post I would ever write it there, no matter how many eyeballs could I attract. The post could be good, but because I have been fed trash on LinkedIn for such a long time, I wouldn't spend a second trying to figure out if what someone wrote is worth reading.

At least for me HN provides me with high quality posts, hence me coming back here for new sources of information. Not saying that all posts on HN are top quality but most of the time the situation is exactly the opposite to LinkedIn. So there's a lot of value to build up your own thing and put work on it.