Deep learning is far from slow down. The research speed has increased a lot in the last 5 years. It amazes me how fast the researchers are able to come up with new things. From one year to the next one there is something shiny and new.

I don't follow very much blockchain but seems like it was 6 years ago

I think most people just don't understand either very well. They feel the hype but are waiting for others to show them examples of what to do.