The fact that Reddit's posts are short and drive engagement; while Hive has longer, more blog-type posts is more a matter of culture rather than something technical. The general format is pretty much the same. There are actually a few subreddits that focus on long-form blogging, story writing etc. Back in 2016, we had an initiative focused on shorter posts, link-shares, memes etc, which proved that Steem could also work in that manner. So, both can work either way, but of course, the majority of content is different between the platforms. We saw in 2017/18 that there were far more casual type posts and shitposts, so I imagine if Steem/Hive ever achieved mainstream adoption, we'd see a cultural shift towards being somewhat more Reddit-like. Similarly, now with Points going out on Reddit, I'm sure we'll see more emphasis on quality on some subreddits there too.

What Hive/Steem does have in addition are certain features from Twitter as you point out - the ability to follow/maintain personal feeds and reblog to them. Reddit has actually tried a Friends feature, but it never really caught on and has been de-emphasized in UI over time. I suspect that's once again due to Reddit's general culture of being a more casual information-based (rather than people-based) social network.