I am not a teacher or researcher, I am a practicing programmer writing code that is used by critical systems as well as ambitious projects that will (hopefully) be used by many real people.
A red black tree is just an example with invariants that everyone is likely to know, so it's a nice way to illustrate the point about the power of types. Known problems are solved problems, and unsolved problems are unknown problems -- so either my invariants' example will not speak to you because you don't know it, or you will reject it because you can just re-use a library.
Whenever there's a static type that Go cannot express (and there are plenty of those!) it is effectively dynamically typed about that property.
We get it. You don't like Go. Some of us do, and would rather have a productive discussion about how to take advantage of it's features and avoid the traps rather than get into a pointless debate about a language that we are highly unlikely to ever use. (after this discussion, I certainly never will)
You are giving the Haskell community a bad image with this kind of behavior, and I kindly request that you not reply to any more of my comments with anything to do with Haskell.
Go is more dynamically typed than Haskell. It isn't a 0/1 thing. Parameteric polymorphism is dynamically typed in Go. Nullability is dynamically typed in Go. These are huge parts of the languages.
Instead of engaging in a discussion, you're repeating mistakes in a condescending tone.
Your last part of the comment is only appropriately responded by "You are giving the Go community a bad image by pounding me with ignorance with every reply, I kindly request that you study the matter before replying further".
It's funny, too, how you talk about "implementing a red black tree" like it's an everyday occurrence. I'm guessing you are a teacher/researcher (in which case this entire discussion makes much more sense). On any application team I've worked with (in the valley or out), implementing a binary tree from scratch would require extreme justification and literally have to be the only way possible to solve the problem.