Maybe the idea is to show that the Apple TV box is more than just an overpriced alternative to Fire Sticks, Roku Boxes etc. Launching a new box/refresh is the proper time to rebrand naming wise but it surely has to be leveraging its other abilities to make the value proposition better:
High performance streaming box
Yes it supplements older TVs where the onboard CPU or software are lagging, some users might want to avoid unnecessary adverts or data collection. Later iterations of paired processors could deliver esoteric HDR formats, high refresh rates, and audio options.
Thread Border Router/Homekit Hub
This is only in the higher end model of the 3rd generation 4k box (with ethernet port) although all versions of the 2nd generation 4k box have it - clearly the driving force behind some users trying to rename it with a variation of the HomePod name. It already is useful as a base unit for Continuity Camera unit for FaceTime calls. I would have thought it's a better idea for all versions of the next AppleTV hardware to have this functionality built in considering the very inexpensive HomePod mini has a Thread Border router built in.
Gaming Box
This assumes Apple keep the next refresh reasonably up to date but using an A18 or A19 CPU has the potential for some high quality games. Technology wise an A19 might compete with Nintendo Switch 2 while M4 (ie a Mac mini) would compete with Xbox Series S. If they were to go for gaming they'd need to reintroduce a fan to the AppleTV.
If Apple were to move this box into the games market then the price isn't too high. Imagine what an M5 Mac mini could do if it was able to boot into tvOS for games. After all, why else would Apple be creating a standalone Gaming app, porting tool kit, etc at WWDC25?