I use an AppleTV connected to a 43-inch 4k monitor [1].
No crappy TV-software and it's a proper screen, with proper response-time to use for the laptop as well.
[1] https://www.amazon.com/Philips-Monitor-Bdm4350uc-42-5in-3840...
[1] https://www.amazon.com/Philips-Monitor-Bdm4350uc-42-5in-3840...