I am old and thus have seen many things come and go. One of those concerns backwards compatibility of various forms.
Without going into ancient history we used to see people quite upset that their fairly expensive GBA flash carts could not do GB/GBC games without emulation, and GBC emulation was not present until somewhat later in the system's life (goomba hit in 2003 and the first alphas for color were 2006).
DS flash carts could not play GBA games, at least prior to them including whole chips on the carts to emulate the thing (and drain the battery), see also things like http://gbatemp.net/threads/can-you-play-gba-roms-on-a-ds-flash-card.50738/
While it might just be because the custom firmware set attracts the cheapest of cheap bastards we also get to look at all the threads with people wanting to play DS games on their 3ds without a DS flash cart.
Thus far I have not seen anybody express upset at the switch not supporting 3ds games.
I am thus forced to conclude something
3ds has no games.
Some might say that is a poor conclusion so I will back up with further evidence. See anybody complaining about a lack of DSi compatibility with things?
Without going into ancient history we used to see people quite upset that their fairly expensive GBA flash carts could not do GB/GBC games without emulation, and GBC emulation was not present until somewhat later in the system's life (goomba hit in 2003 and the first alphas for color were 2006).
DS flash carts could not play GBA games, at least prior to them including whole chips on the carts to emulate the thing (and drain the battery), see also things like http://gbatemp.net/threads/can-you-play-gba-roms-on-a-ds-flash-card.50738/
While it might just be because the custom firmware set attracts the cheapest of cheap bastards we also get to look at all the threads with people wanting to play DS games on their 3ds without a DS flash cart.
Thus far I have not seen anybody express upset at the switch not supporting 3ds games.
I am thus forced to conclude something
3ds has no games.
Some might say that is a poor conclusion so I will back up with further evidence. See anybody complaining about a lack of DSi compatibility with things?