Slingbox and Mac users

I f you have the Sling application installed on an Apple TV 4K (tvOS 11.0+) or Sling app for iPad/iPhone (iOS 11+), you can stream that content to you Mac. You will need to be running macOS Monterey or later for this functionality. Subscription likely.

See Use AirPlay to stream video or mirror the screen of your iPhone, iPad, or iPod touch - Apple Support

The Sling for Mac application is not compatible with macOS Catalina or later. Sling is discontinuing its Slingbox products too.

I quit watching Sling and now watch pluto.tv (free) via a browser.

Sling is moving away from physical Sling boxes to become a subscription streaming service, and to that end, you can watch it directly in Safari or Google Chrome on macOS releases after Mojave. That is your only computer viewing model (that I am aware) beyond macOS Mojave, unless you want to maintain a WIndows 10 computer on which they still provide a Sling app that can access your Sling box. Sling is evolving, and you may need to do the same with respect to how you access their content.

Until the condo was sold in Florida, there was a Sling box there, and one 60 miles distant from here, on two different cable networks that provided rich programming over the Internet to local Sling applications on macOS. But I have moved on from Mojave, do not subscribe to Sling's streaming service, and no longer watch it in favor of other streaming sources.