Montage is capable of streaming video files from your computer to an external screen.
However, various factors need to be considered. If streaming movies from Amazon Prime, Netflix, etc., is the main use-case, perhaps, Montage is not the right device. It is designed for business/education-oriented environments, where the main focus is presentations, collaboration, occasional videos, and similar use-cases related to meetings and classes.
Digital Rights Management
There are some limitations services offering DRM (Digital Rights Management) protected content. This means that certain streaming apps, such as, but not limited to, Netflix, Disney+, Apple TV+, HBO Max require other DRM systems and thus are not supported.