should have ability to stack videos

This is probably what Bob is talking about:  FROM PSE ORGANIZER 2024:  You can create albums (groups of related items- videos, or pictures all taken at one spot) easilly.   Just like the albums you can create from your photobin in PSE.

I'm pretty sure it will never happen in Photoshop Elements-- it's the name "Photo" Shop Elements.  Adobe has programs than can handle video, PSE has never been meant to use or edit videos. 

Premier Elements allready can do it- Adobe calls the guided edit in premier elements "picture in picture" it's also called "composting"-- Premier elements is quite good at it:  Please remember PE is designed for the average consumer, not a professional.

I grabbed a couple of quick videos and made this in Adobe Premier elements to show you:

https://youtu.be/nDRZ-5NP25U?si=mDz0XHrbYBL5-ZzQ

I think the OP is talking about stacking in the Organizer, and it is not possible there.  Although, there was previously an automatic stacking of clips in the Organizer when saving a project after using one of PRE's features.   I forget the details. Several users complained about this.

I think this is the first time I have seen this request by a user.  It seems like a sensible request and I will pass it along to Adobe.

You can do that in Premiere Elements.