> What's the role of an academic journal in 2020?

For me, trustworthiness. Not all journals are equal but some are held in such high esteem that I would grant a lot more credence to the findings of an article published in a journal than one self-published.

I have neither the time or will to assess the merits of each individual who might publish something. If a name is sufficiently big within a field, it's usually in a sufficiently big journal; on the other hand, I would treat a self-published article with the same level of skepticism as those low-tier journals that happily publish pseudoscience as fact.

Call it snobbishness if you will, and I'm fully aware that academia is full of it, but that's the role that a journal fills for me.