even when i was younger i hated nintendo's games so the DS platform was never for me. The Wii is another story however. it's an ancient machine and it will always have a homebrew scene, which i could not exaggerate the importance of to me. They should make a new edition with better software just for people to tinker with and do as they like.
I was about to bring this up but the 3DS did have a big homebrew and emulation scene I believe. By about 2017 the Switch had come out and ended up being a hit, but they wanted to hold on to the 3DS in case the Switch flopped--even though I think Nintendo had known about shit like the Freeshop for at least a bit. It had become one of those public piracy things where its real easy to find guides for it but all of them had "WE TOTALLY DONT RECOMMEND AND HOLD NO LIABILITY IF YOU DO THIS ITS TOTALLY ILLEGAL (but heres how to do this

)" disclaimers, but for some reason, I think something to do with how their 3DS eshop was set up to work with the hardware, they couldnt to anything about it.
Very early on the only game worth playing was Ocarina 3D and it stayed that way for a bit.
Now that you mention it I remember that, up until around 2010 or 2011 and the holiday season combination of both Mario 3D Land and immediately after that, Mario Kart 7, plus a price cut, really got it running. Damn I have memories of getting and playing it that Christmas, then going with my family to a Trail of Lights type thing and checking for my first streetpass. Takes me back.
I hated the streetpass because I never got any, but thinking back on it, it made me bring it with me to a lot of places and make sure it was charged and shit, I had it with me through good and bad times, different people and phases, events, in a different way than your phone, remembering popping out and playing it for a bit whenever I had downtime even with other people, giving me some real "Damn, 10 years?" feels. Plus I had the Hot Rod red Mario Kart DS from when it launched before that, I played with it so much as a kid all the paint faded off from me keeping it in my pocket.