I feel like giving this a serious reply, despite the thread being a joke.
I think what I like most about Nintendo consoles isn't the stuff that makes them so beloved (but I could be wrong).
But perhaps the same is true (to a lesser extent) in regards to my taste with sega consoles too.
Bullet point version
NINTENDO
I view the NES and the SNES as the only "real" Nintendo consoles.
I don't really care about first party Nintendo games beyond SMB1 through World and Link to the past.
When playing the SNES, it's going to be an action or shooting game 95% of the time (which many claim are departments that SNES lacked in when compared to generational peers. I don't fully agree).
I grew up as a "Nintendo kid".
SEGA
I don't think there is a single title developed by Sega that I "love", but they definitely have developed more games that I "like" when compared to Nintendo.
Saturn > Mega Drive > Dreamcast for me
I appreciate the companies arcade-centric roots and these roots are plain to see when it comes to titles they've developed, published, ported, or green-lit to release on their consoles.
I never viewed sega as "cool" until I got older.
I find myself playing sega consoles a bit more than nintendo consoles because it's usually a port of an arcade game (developed by a third party).
I still don't prefer one company over the other.