Try using 4chan and ignore the crap you don't care about. It's exactly like reddit, everyone says stay away from the defaults. In 4chan's case, stay away from /b/, /v/ and /pol/ and you're unlikely to see anything graphic or demeaning beyond general discussion boards...
Projects I know that were born on 4chan: tox.im - /g/ TurtleCoin - /biz/ NetRunner - /g/ Others mentioned in the article, notably project chanology.
Editing this comment just to say that my point wasn't that toxicity, racism and sexism are okay to just ignore... my point was we already ignore that everywhere else on the internet. Look at youtube or reddit comments. If you can't see how it's the same you're just better at ignoring it on your platform of choice. I'd say it's more concentrated on 4chan yes, and I've probably gotten pretty good at filtering it out myself. But this problem is all over the internet and writing a piece about how 4chan "needs to grow up" isn't much of a revelation. The whole internet needs to.