This obsolete port is still included on far too many TVs

For a very long time, you could safely assume that any TV you bought would have a 3.5mm stereo jack. It was the default wired option if you didn't want to use built-in speakers. Better options have been around for decades, but not everyone was willing (or able) to shell out for, say, an optical-basedDolby Pro Logic system fed through a receiver.

Source : https://www.pocket-lint.com/stereo-jack-on-your-tv-is-obsolete/