But what about the 3DS and New 3DS?
PS4 and PS4 Pro? XBO and XBO X?
Those are all more powerful variations of their original systems.
3DS and New 3DS are a bit more like the GB and GBC, as in they had games exclusively running on the later version, so if you go that route at least 3DS and New 3DS have to go the same way.
Except that the PS4 Pro and Xbox One X don't have exclusive games, the Game Boy Color had a lot of exclusive games that didn't work on Game Boy.