I can understand the whole "keep the old chassis to transition to new internals" idea, but I really hope Apple will give the (hopefully) 2025 M3 Extreme Mac Pro chassis a redesign... ;^p
I expect we'll get the same chassis the next revision too, at least. Tim Cook's Apple loves their legacy form factors to save money (and frankly the Mac Pro is the one place they absolutely should stick to the same form factor. It's well-designed, flexible, and most every professional appreciates a new, faster model that can easily slot into where the old one was without tinkering.)