He's explicitly rude. Sets up a strawman argument with the developer who can't imagine programming without generics. Mocks the people who want generics. Gasps in faux disbelief that it could be solved by types.
And then, when he goes in for the kill, to show once and for all that generics are pointless garbage:
He attacks type hierarchies and inheritance... completely missing the point by conflating parametric polymorphism and subtype polymorphism.
I think "Fuck generics" does a decent job of summarazing the rudeness, misinformation and ill-thought out arguments that the article contains about generics.
If you think you know how I ought to spend my time, come over and mow my lawn while I expound on the problems of dev entitlement culture.
I'm fine with RSC, Commander Pike, and those other benevolent dictators continuing to make much better decisions that I certainly ever would and more importantly to be super careful with what they add to the language. I write Swift, JS, objC, and Go. Go is the preferred language because it's simple and I have the entire SDK in my head.
I use Go a lot. I can't say i've ever run into not having generics being a huge deal.
Let's face it, for most programmers out there, generics is for type safe collections. If slices and maps weren't built into Go then i'd prolly have moved to something else.
That said i'd like to see more built in data structures