It is the big obvious current example where the ideological battle is between "second wave" and "third wave" and the first wave is barely mentioned. I encounter it in relation to the UK social justice Twittersphere, which is tangential to the more Kankri Vantas stretches of Tumblr. (Or, more accurately, the Porrim Maryam stretches.)

Edit: Can anyone think of another field described as having numbered waves where the battle was between second and third?