Personally I think no one has emulated them because no one wants to be responsible for emulating games where men show thier junk. So I say if someone emulates them only do the one where you pick the differences between the naked women it's the only one that is really good anyways.
Nah that's not it at all.....
There are several gambling related games on those systems that (gasp!)
don't involve nudity at all. Also there are a lot of trivia games.
The main thing is that these games are rather simple and mostly consist of static pictures and text. Take that and the fact that most of these games are very dated at this point (making the trivia games worthless and the pr0n often pixelated and ugly) these games just aren't fun to play, nor are they technically interesting from a hardware nerds pov.
Unfortunatley, most systems don't get emulated unless the games are either pretty, the hardware is interesting, or the games are fun to play.
Look no further than the descrete logic games.... Because they are rather ugly and some people (not me) don't find them to be very fun, there are only a handful of simulators, and most of those simulators are a version of pong.
So if someone wants this done, they are going to need to find a emulation dev that actually likes those touch screen games for one reason or another, and raise funds to get them the hardware to research.