This guy is factually wrong. Knots runners hold the exact same chain data as core runners on their drives.
Getting simple facts about how bitcoin works wrong isn't great for your argument.
Discussion
I think you're making an assumption. Time may prove you right, but for now it's still an assumption. Perhaps I am too - I mean, I don't think Knots will continue to just make little tweaks after 30. The fork in the road may or may not entail a hard fork, but I think the code of knots and core go separate ways soon.