Nothing in that article says anything about there not being a sequel to X-Men Apocalypse, nor is there anything in it that says that we're absolutely getting a New Mutants Trilogy.
The only thing that article tells us is that Josh Boone PITCHED New Mutants as a trilogy of stories and consequently has ideas in mind for 3 movies; it says nothing about whether or not he'll actually get to make all 3 of the films he's got story for.
The only thing that article tells us is that Josh Boone PITCHED New Mutants as a trilogy of stories and consequently has ideas in mind for 3 movies; it says nothing about whether or not he'll actually get to make all 3 of the films he's got story for.