People are confused, thanks to good marketing from companies. eARC is HDMI 2.1 but can be used on a 60Hz TV because it supports 7.1 audio pass through as well as 120Hz on panels that supports it. The 7 series, 8 series and the Q60t are 60Hz panels. Here’s the benefits, if you have a streaming service that supports Dolby Amos your TV can’t provide 7.1 so you would use HDMI eARC to send the 7.1 sound track to your audio equipment. I hope this helps and here’s the link to Samsung article.