This may in fact be a feature rather than a bug. "Anyone in the world can slam their crappy reply to my post in my face and create a message, notification to my phone, etc." is probably a bad model. "Anyone in my personal friend list" is better but sometimes still too broad.
Web logs had a characteristic where you kinda had to put a bit of elbow grease into seeking out replies, and that isn't all bad. There are plenty of instances in the old web log communities of some monomaniacal troll paralleling some bigger blog's every post with their inane (if not "insane" as my swipe keyboard started with) replies, but mostly nobody has to care. You visit the original web blog and you don't have to see it under every post. Even the original author can pretty much just get on with life without having to worry about it. This is not something "conventional" social media does well.
I remain unconvinced that the model of pushing replies into everyone's face, bundled with the original content, is the best or only model for social media. It's probably a nontrivial part of the reason everything seems so homogenous nowadays... it really is. The same regress-to-the-mean in every "social" interaction because it's the same regress-to-the-mean people and patterns in every single one. Give people a place to be themselves without a hundred people tromping in and you get those unique voices back.
I understand why you may say that, but it's not about misanthropy or introversion. It's about scaling. If you are in a situation where your posts get maybe four comments, all from your real-life friends, all generally positive, hey, great. You don't have a problem.
But let's say you're writing a technical blog, and you've picked up 10,000 readers. You may get a few hundred comments. And they're going to look like an HN discussion area; a few positive hints, but mostly negative comments. If you don't moderate, they're going to start to tend to actively insulting comments as the inevitable escalations develop. So maybe now you need a moderator. Who wants that.
If anything, it's the misanthropic ones who don't care! They're the ones willing to host a brawl in their comment section and give as good as they get, if not better. They're the ones who don't lose any sleep over ban-hammering someone just because. It's the normies who start having problems here.
The social media you describe and are implicitly praising promotes drive-by interactions and tons of shallow connections. The weblog community structure promoted fewer, but stronger connections. You might not have realized this, but a lot of "web rolls" back in the day weren't just "Hey, you may be randomly interested in these blogs"... after all, why would anybody put those up? They were actually a community. Conversations would wander back and forth in these communities for days at a time on a topic, with cross-linking, rebuttals, amplifications, etc. And it was nothing like the heat-but-no-light of a twitter reply chain.
I miss it. It was much nicer in a lot of ways, and could have been improved even more. But it takes a bit of a critical mass, maybe not a ton, but even so we've lost it to an endless chain of mostly vapid, regress-to-the-mean boring homogeneity.
Much later followup: FWIW, I blame a very popular misunderstanding of "free speech". Free speech means you can have your space to talk, and in that space you can say most whatever you want (subject to some legal restrictions like direct death threats and other issues), and anyone who wants to see what you have to say can come see.
It does not mean that anyone who says a thing online, like a blog post, newspaper article, government report, etc. is obligated to host a comment section that allows anyone with a keyboard to put their speech right next to the original topic, on nearly the same footing. I think the all-but-subconscious idea that comment sections are somehow mandatory, or the sine qua non of "free speech", seriously hobbles people as they try to design communities.
Weblogs empowered the individual, and then we could interactions from there. Comment-based designs pull everything down to the same level. Mastodon et al still go in the wrong direction, in my opinion.
Web logs had a characteristic where you kinda had to put a bit of elbow grease into seeking out replies, and that isn't all bad. There are plenty of instances in the old web log communities of some monomaniacal troll paralleling some bigger blog's every post with their inane (if not "insane" as my swipe keyboard started with) replies, but mostly nobody has to care. You visit the original web blog and you don't have to see it under every post. Even the original author can pretty much just get on with life without having to worry about it. This is not something "conventional" social media does well.
I remain unconvinced that the model of pushing replies into everyone's face, bundled with the original content, is the best or only model for social media. It's probably a nontrivial part of the reason everything seems so homogenous nowadays... it really is. The same regress-to-the-mean in every "social" interaction because it's the same regress-to-the-mean people and patterns in every single one. Give people a place to be themselves without a hundred people tromping in and you get those unique voices back.