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You can have monads in clojure (eg: http://funcool.github.io/cats/latest/#monad) but the problem I see is that they are infectious and kinda force you to use them everywhere. In other languages, it's more palatable because the compiler checks for types, and normally there is some sugar to make it easier on the eyes.
> So are the , , and types ? Clojure has collections like [vectors], {maps}, '(lists/seq), #{sets} and a bunch of primitives that can fill up those collections, so I'm not certain how this relates exactly...
They are. It's the generic notation that you'll find in Java, C#, Rust, etc.. They are statically typed languages, so instead of just saying [vector] like in Clojure, you would say Vector, where T is the type of the things in the vector. Vector by itself is not a type. You can think of it as a function that takes a type and returns a type: with Int, you would get Vector, with String, you would get Vector. This isn't limited to collections: Option represents a value that may or may not be there, Result represents something that can be either a result, or an error.
> Are promises and futures always monads?
Not all the time. For example, JavaScript promises aren't monads. There's a relatively popular discussion about it here: https://github.com/promises-aplus/promises-spec/issues/94.
As another example of a monads, there Option, called Maybe in Haskell. It's used for a value that could be there. Java has Optional that looks like it, but isn't a monad since it doesn't follow the monad laws: https://www.sitepoint.com/how-optional-breaks-the-monad-laws....
A good way to think about monads is to think about them as mathematical objects. They respect some rules, and thus have some properties. When you're implementing something in a language, like promises, you can choose to have them respect the monad rules, so that they can have the monad properties. You can also not do that (like they did in JavaScript), and so people won't be able to use them like monads.