This is subjective. I personally always loved upgrading the hell out of old PC (install the maximum possible memory and CPU after patching the BIOS and soldering the socket, add a SATA card to a computer which only had IDE etc).

I feel like there's something different between doing this to a PC, which is in some sense designed to be upgraded, and doing this to a game console.

Indeed. Doing this to a game console is more "badass".

console of theseus

Not of Sisyphus hopefully :-)