There are vertical grand pianos from yesteryear where that’s exactly how they’re made - keyboard at the bottom and strings up to the ceiling. I’ve only seen ones about 6ft tall though, the same length as most grand pianos.
I think this dude is just being “extra” - as the kids say.
https://www.tefaf.com/art/details/tefaf-maastricht/renar/florentin-baudet-grand-vertical-piano
