For black holes, most scientists seem to agree that black hole singularity are not a real thing but an artefact of our lack of understanding of gravity at small scales, a problem that quantum gravity intends to solve.
Same thing for technology, I don't believe in "the singularity" as a real thing. If, as the article says, the singularity will happen in the next 20 years, it simply means that the model they used will break down in the next 20 years and if we want to look further in the future, we need a better model, that's all.
There may be a massive advance in AI, we may see AIs designing AIs, but saying that it will quickly result in god-like beings is naïve at best. The most likely result is that even if we manage to create a superhuman intelligence, it will hit a roadblock and end up only slightly more intelligent than we are, and clearing that roadblock will require time and effort, and will only uncover another roadblock. I believe we will make progress, but it will be a step by step process, no singularity.
And if you think about it, we already created a superhuman intelligence in the form of a computer assisted human. Computer assisted humans can solve problems neither can solve by themselves. AGIs, if they ever become a thing, will not be better than humans at everything anytime soon, I'd think of them as a really smart, but nerdy and awkward coworker, the 100x programmer maybe, but who needs a boss to put his skills to good use. And here I am speculating, a lot, further than that, I simply don't know, or I can say that there will be a singularity, which means the same thing.