I think a lot of this recognition that we will need to replace academic journals soon has been the recognition that bioRxiv, psyRxiv, and medRxiv have not been the disasters many thought they would be*. I think a lot of people thought that peer review was critical to the success of the enterprise, and therefore we had to put up with the journals because we needed the peer review gatekeeping. However, it has become clear that (within field), labs can mostly do their own peer review.
It is not clear what we can do about science outside field. As a scientist how can I know whether to believe something outside my immediate field. And how should we control what journalists, politicians, and clinicians trust, given that they do not have the training to do their own "in-lab" peer review.
Nevertheless, importantly, now that we have preprint servers and can compare pre- and post-peer review, it is pretty clear that peer review isn't doing much, which gives us the ability to say that the costs (excessive publisher profits, reviewer time costs, etc) are not worth the gains.
Yes, I know, arXiv has been around for many many years. But people somehow thought biology, psychology, and the other non-physics fields were different. ¯_(ツ)_/¯