But isn't so much journalism nowadays characterised by unsubstantiated speculation? (i.e. propaganda, if not simply clickbait filler pretending analysis)

It seems to me your criticism amounts essentially to your dislike of the thesis of this piece. This can be legitimate, but not what you've argued here.

Isn't this piece an example of precisely the supposed promise of the internet, in the sense that journalism becomes democratised and anyone can publish and disseminate analysis, which can be evaluated on its merits rather than institutional validation and inertia based on opaque criteria? (I would of course argue the aggregated needs of capital, but I won't force that in)