Feel feel to ask questions in the comments about the resolution criteria if there's anything you're wondering about.

If it can play games that the old Switch can't, then even if it's fully backwards compatible, I'll probably count it as a successor (as in the case of game boy advance to game boy colour, or wii to gamecube).

If the Switch can play all the games that the successor can, then I probably won't count it (e.g. 2DS, Switch OLED, Advance SP).