Usually, the homebrew community grows, and softmods/exploits become more plentiful after a console becomes discontinued. Note how many things came out for the Wii after 4.3 was confirmed to be the last system menu version, how many people got into the original Xbox after it was discontinued, how many flashcards, repros, and various other homebrew enablers came out for the DS/DS Lite after it got discontinued.. Personally, I have hope for the future of the 3DS modding scene. I'm already pretty impressed with what they've done so far.
In a strict numerical sense then sure (we don't tend to see data be lost and thus anybody that adds anything adds to the sum total). In a more practical sense things rarely get better, never mind radically, afterwards for the modern consoles. You get the odd things for the cult classics (see Dreamcast) and random devs trying their hand at stuff to test their skills or something but if we are looking at things that either were during their day a homebrew powerhouse, or had enough grunt to act as one but for whatever reason did not see a major scene (xbox 360 and maybe a slightly lesser extent PS3) have not seen major resurgences or things really pop.
DS/DS lite. Yeah a sea of awful timebomb things with R4 in the name. The homebrew scene had seen Apple put two in the back of its head and was bleeding out fast (only for Android to do that in turn to Apple).
After that big DSi and 3ds update slammed the door shut on most of the big players in flash cart world that were not Supercard (the DSTwo managed to stick it out) we only saw dross -- if you know a nice R4 named thing with as nice a feature set as late stage EZ5i kernels, M3 kernels and the like please do share, and if you have a nice line on DSTwos then probably want to keep that to yourself, buy up the lot and make yourself a tidy profit.
Xbox
https://www.xbins.org/index.php?action=catsearch&searchtxt=XBOX
Some nice stuff but mostly a few incremental builds.
If we take the end to be 2010 with the shutdown of online services/Live for the original xbox (
https://www.gamesradar.com/uk/exclusive-interview-halo-2s-final-players-share-their-stories/ ) then even less than that, go a bit more modest and it being after the 360 had properly exploded onto the Scene and it is still not great.
XBMC (these days Kodi) was the xbox's crown jewel and it parted ways with the xbox not so longer after (not without reason) leaving groups like t3ch to backport the changes. Good stuff but nothing really radically changed following that (and this was during the rise of H264 video that it sort of maybe half played, certainly was not a "grab a Scene encode and play it" like it was for the AVI-xvid era (though such things did stick around for a while to come so you could still have a good time).
On the Wii I am less familiar with that one on a blow by blow account level. However from the point USB loaders got nice cover art and maybe the nerfed gamecube options got late stage then was there really all that much? Emulator development was mostly people fiddling with N64 injection (I installed a bunch of stuff when modding a friend's wii with twilight princess, could play basically all the games then I could today, maybe with a slightly shinier menu and the lack of a bug or two that the hardcore might notice but still), media players never got to anything like XBMC level as much as proof of concept dressed up a bit (which made for something workable but not as shiny as XBMC/Kodi/forks thereof).
From where I sit then the 3ds has little to offer in terms of being a powerhouse (it was outclassed by phones almost from day 1, certainly by year 3 it was trailing all but the nastiest android phones by some margin).
It does not have any particularly radical features that make it a compelling case.
While the lack of buttons on devices concerns me there are enough bluetooth controllers out there (was round a friend's the other day and his kids were all sitting there with PS4 controllers playing on phones) that even that is not going to be a major draw.
There is a barrier to entry that other devices lack both for the homebrew developer and for the would be audience, who will likely not pay you anything (nobody jumped to apple because they wanted to buy a mac mini/build a hackintosh to compile things and pay apple annually for the privilege, or to android because Java is such a nice language with minimal overhead).
As far as going in a pocket then phones do that, and also I don't think I have seen anybody seriously carry a handheld in their pocket for more than a trip to the kitchen and back, to the car, or to bed at night in a pocket that is not a serious coat since the game and watch. Bag, carry case, your hands or nothing.