I detest social media and want no part of it, but I've read and watched videos about what you just mentioned, the dopamine rush from those likes and other forms of affirmation on various social media sites. I tend to think that's a very unhealthy way to stimulate the pleasure center of your brain--or at least it could be if you become dependent on other people's reactions to your posts/pics/videos/whatever in order to feel pleasure (or to feel validated as a good person).
I also don't like too much to participate in social media interaction unless it's necessary with either work or communicating with loved ones. I do appreciate what it has done to each and every one of us when communicating but I think the part of us, being human, makes us vulnerable to social hacking and the likes.
I was here before the merit system launched, so I don't really need anyone's approval to boost my ego because I never got that before--plus I'm pretty confident that at the very least I'm not a shitposter.
I think we all know who are the ones who really put effort into the post and not just repeating the same sentiment by everyone who posted before the poster or something. I believe in the added value to which you can improve the topic and share your input towards it.
I can go weeks without getting a single merit and still know that I put a decent amount of thought into my posts and that at least they're not complete crap. And man, I haven't even been trolled by the likes of cryptohunter (who called me a troll and a shitposter if I'm not mistaken) in many months, so I'm content with that.
People who attack that way are probably insecure themselves. As long as you know that you are doing the right thing and you know the truth in what you do, you shouldn't be affected by those kinds of things, right?