Unable to adjust the playback speed of podcasts

You cannot change the playback speed of a Podcast in iTunes and have never been able to do so. The discussion that you were reading in your video is misleading (in several ways).

The only speed adjustment is in the Podcasts app on Apple's portable devices (iPhone, iPod etc.). There is no speed adjustment in iTunes, either in the Music library or in Podcasts.

Would I be correct in thinking that prior to the start of your video, you had already changed the media type of the podcast you're listening to, to Voice Memo? If not, it is a mystery why it already stated Voice Memo when you switched to the Options pane. Changing the media type won't work.

So to achieve what you want, your only option would be to download the Podcast to your iTunes Library (and the one you're playing was not downloaded, it was being streamed), add it to your iPhone, iPod etc. and then change the playback speed while it's playing. On those portable devices, at the bottom of the Now Playing screen (below the volume bar) you will see 1x. Each time you tap on it, it cycles to the next option: 1½x, 2x, ½x and back to 1x.