It's not really anything you can do if people aren't coming and engaging on your posts itself, like it happens some times, sometimes I may write something I think will get a lot of engagement and it ends up only getting a handful of comments, meanwhile something else may surprise me, etc. It's the average I guess that matters and as long as that is trending upward somewhat along with active userbase then it's a good sign.
I'm more against authors who think that their content in and of itself is worth all the rewards, where they don't care/bother engaging with people engaging with them or people in the same circles/community who also post about something similar/share interests. If you're not giving anything back in terms of your time/effort to appreciate others but expect to continue earning same if not more rewards like everyone else, then I'd hate to break it to you but those rewards may not be fairly earned.
It's different if you have a social presence outside of Hive and you're literally that popular that you can't engage with everyone all the time, there's other ways to then bring value to the ecosystem and I don't expect people to judge or downvote them for not engaging, but this is a minuscule example of affected authors here, most are just regular people without any influence outside the space.
Generally, new hive users tend to make a post then leave. All of your points are taken and will be added to the orientation that I will make for those who I will invite soon.
Time and Effort, I see most look into the written content of the blog. I want also to add the time and effort for lay outing a neat blog. Like just keeping text justified or using headers to separate thoughts within a blog.