Also you're leveraging anonymous function syntax which is, interesting, to say the least. In Java 8- you'd have to write boilerplate class named after a pattern. Lastly creating something from outside information was done since forever, it's trivial when you don't invent ceremony around it. Hence my conclusion, it's a waste of time and effort.
No, because you still need to name the thing the function is assigned to. What exactly should the user of the function call it? thingMakingFunction? You need a consistent way to refer to "a function call that creates an object in a particular state" and factory is as good a word as any.
Yes, in Java 7 or below it'd have required more verbose syntax. So what? That came out 8 years ago and Java isn't the only OO language with a notion of factories. C# had delegates much longer than Java had lambdas, and it also needs a way to talk about "a bit of code that produces objects complying with a contract", so also talks about factories.
Also you're leveraging anonymous function syntax which is, interesting, to say the least. In Java 8- you'd have to write boilerplate class named after a pattern. Lastly creating something from outside information was done since forever, it's trivial when you don't invent ceremony around it. Hence my conclusion, it's a waste of time and effort.