I think MGTOW are different from herbivore men. I'm not expert on either group buy my understanding is Herbivore men are men that don't or never have sought out relationships with women, while MGTOW is more comprised of men that have had bad relationships with women and decide not to pursue further relationships (especially divorced men).
Do they not pursue relationships, or do they simply re-prioritize? I think it's healthy for people to develop their independence, and I think you need to be independent as a person before you can be interdependent as a couple - as opposed to need a mate to function as a person.
There is a similar movement growing in the US which is called "MGTOW", men going their own way: https://en.wikipedia.org/wiki/Men_Going_Their_Own_Way
Personally, I'm a bit scared that we're going towards a culture of increasing isolation and tension between the genders.