It is possible to create a game from scratch using only the device's hardware.

I've always wondered if it's possible to create a game from scratch using only the console's own hardware, without needing a "dev kit" (which are known to be quite expensive and not readily available to the general public).

For example, using the Xbox developer function, would it be possible to program or create a game (it doesn't need to be a AAA title) for this console using only the hardware?

For example, an Xbox Series X, which is quite powerful.

Regarding the use of an engine, can the console itself run it in "creation" mode? Or would we still depend on extra hardware (either a PC or a Dev Kit)?