Maybe we are indeed in the beginning of a trend reversal, but we don't have enough data to support that as far as I know.
However, in this case, the author predicted the downfall of a huge company. If its business starts failing by any reasonable metric, its stock will fall very fast and very far.
This isn't to say that it's not without its uses, but we should be aware that it has huge problems even if we don't know of a way to fix them yet.
By definition, every non-ideal behavior of real markets is a “market failure”.
Real markets, as opposed to Econ 101 idealized ones, are full of market failures, both due to structures that Econ 101-level analysis ignores about basic market structures and human irrationality.
There are also lots of examples there of people gambling on TSLA shooting to the moon and making a killing this year.
Anyone who cannot predict such events can write articles for a magazine claiming otherwise. At least it helps sell their speaking and consulting engagements.