How “big” are your movies and tv shows? If they are 4k UHD remuxes then Nvidia Shield Pro or Apple TV 4k behind a firewall to block external internet is your best option for performance, usability, and privacy. You will want to ocassionally allow it internet for software updates. Kodi, a mini pc, raspberry pi, etc. would be more private but you trade off a seamless remote, easy interface, and streaming codecs (e.g., dolby vision).
How “big” are your movies and tv shows? If they are 4k UHD remuxes then Nvidia Shield Pro or Apple TV 4k behind a firewall to block external internet is your best option for performance, usability, and privacy. You will want to ocassionally allow it internet for software updates. Kodi, a mini pc, raspberry pi, etc. would be more private but you trade off a seamless remote, easy interface, and streaming codecs (e.g., dolby vision).