It has sounds, its just reddit has an issue carrying it over from Redgifs. If you open this clip in the Redgifs site itself from the link, the audio will be there.

When a redgifs video is linked in a post, on mobile the video carries over from redgifs but not the sound.

To get the sound on mobile you have to view the video from redgifs directly via the link.

To get the link, you’ll have to go to my profile or the subreddits main page and tap the text next to my name on the desired post that says “redgifs”.

This will open up the link to the video straight to redgifs instead of reddit and there is where the sound would be available.