"I do tell people when I upvote and follow them, but it's simply my way of saying "hey, I like your content!", and I do it after actually commenting on what I read and legitimately engaging with their content before I do." - and that's the difference right there.
i'm all for people telling me they liked the content (but be specific and show me you actually read the post) and that they're now a follower (cool; more than happy to check out your profile since you authentically engaged with my post)...but it's these skeletal posts that are more like bug bites than anything substantial that are so prevalent and annoying.
and yeah...i had that same early bump when i first came on too. it's been hard to get a lot of exposure since, but that's part of the deal. you have to engage, you have to legitimately talk to people, you have to consume what it is they're putting out if you expect people to consume what you yourself are posting up.