The launch of hundreds of new generic top-level domains – like .cooking and .horse – has not been as successful as the domain name industry expected
Well no. Of course it hasn't. Those in the industry who expected it to work were being blinkered by greed.
The reality is that the massive expansion of top-level domains was always a bad idea. The only reason it was done was as a cynical money grabbing ploy by the registrars. If it's back-firing on them now, then I'm not going to cry for them.