It probably depends on exactly what kind of SSH tunneling you're doing. For example, if you're using OpenSSH's
-D option to make SSH act as a SOCKS proxy, then you shouldn't need to make your Mac act as an AP. You should just need to make sure your Mac is reachable from your Apple TV (e.g. have them both on the same home network), and configure your Apple TV to use your Mac's IP address as its SOCKS proxy address.
Configuring advanced networking things like SOCKS proxies on tvOS is done like it's done on iOS: by creating a special "configuration profile" (
.mobileconfig) file, and installing it on the device. Apple has a Mac app called "Apple Configurator 2" that can be used to create and install these profiles. You'll need the right USB cable to connect your Mac to your Apple TV for profile installation.
Most of the details you'll need are in this Apple support article:
Use Apple Configurator to install a configuration profile on Apple TV
Caveat lector: I haven't ever set my Apple TV to use a Mac's SSH tunnel as its SOCKS proxy, so I can't vouch that this setup will work, but the theory makes sense.