As to #4, kids, remember there is a big difference between
A) Posting, on your own blog, things like “Boy do I sure wish the most popular ship in my fandom wasn’t the pedophilic/incestuous one” or “I wish people would tag their content appropriately more often so I can properly block it” or “that piece of professionally made media is problematic because it has pedophilia in it” or even “I really hate it that X kind of content is so prevalent in fan-works today, it’s dangerous because Y,” and
B) Posting callouts for individual named artists accusing them of being pedophiles or supporting pedophilia, incest, or abusive relationships in real life because they create content of fictional ships.
There’s also a HUGE difference between BOTH of those things and
C) Going into people’s inboxes to tell them to kill themselves because they drew something you don’t like, even if the reason you don’t like it is moral outrage.
Yes, EVEN IF in real life the things they drew are illegal and generally considered bad such that your moral outrage, if it was directed at these actions in real life, would be entirely justified. It’s NEVER okay to try to suicide bait people. It’s NEVER okay to threaten people. That’s a human person behind that Tumblr account, and it’s important not to forget that. If someone posts content you hate, block them, block their username, block the tags for that content, hell go on your own blog and say “I HATE THAT KIND OF CONTENT A WHOLE LOT!” But don’t attack someone over fiction. It’s just pointless and drags down fandom culture as a whole.
You have every right to your outrage, and you have every right to not like to see that kind of stuff and to talk about why. But you don’t have the right to hurt people over it. Take care of yourselves, absolutely! But remember it’s not the job of strangers on the internet to do it for you!