The clip, in this case, is just a PNG image of a logo. However, as I stated in the video the type of layer that it is doens't matter at all. It will happen to any kind of layer on your timeline, because I have had it occur with PNG's, JPEGs, MP4 clips, MOV files, Sequences, nested comps, Graphics that are created in premiere, Text layers... any kind of layer that Premiere will accept. Something I forgot to show in the video is that when I move the text layer on top of the smaller, PNG logo layere, the text layer remains just fine. But when I move the PNG back on top, it cancels out the text layer, beneath it.
What's on a higher track will cover anything below it unless you have a mask with lowered opacity on the upper track so show the lower track content through the mask.
If you are building a graphic, it's best to use the Essential Graphics panel in the Graphics workspace, and build it as one layer/item. You can add things like png/jpg to them, layer different elements of your graphic. Set opacity and such.
And then you have only one item to copy/duplicate/reuse as you wish.
You can have complicated graphics with logos and text and images sliding in and out separately.