Discord is popular as the response is almost immediate, while writing posts can be a hit or miss.
Don't I know it :) And yes, there are many ways to engage. There are heaps of posts, but so many of them are the kinds of posts that don't add a lot of value to the reader, it is more of a schedule of getting a post posted for the creator to earn. For the larger-staked SPL players, those earnings are insignificant, but what they can add to the community is far more valuable for everyone. It is like how I believe Hive witnesses should be posting semi-regularly and giving their views, because (almost) anyone can run a node.
Most of my engagement is through comments and reading other people comments.
And this is hugely valuable too, because when people do take the time to write something interesting, while the vote value is great, the engagement is what keeps them motivated and willing. Votes never hold a creator's (most) attention for long.
Post engagement is super important. I get a little disinterest from writing as I do get some votes which I definitely appreciate, but just zero comments. After a while, I feel like I am just putting something out to get votes, which just feels like not super worthwhile.