OSLauncher can be blocked in mere seconds if they felt like it. They just don't care, that's all. (Then again, have we even showed it to them?

)
As for the Prizm, I don't believe that people will get attracted because of the games and colorful screen. It all boils down to the majority and what's on the "back-to-school list". If it says that students should get a TI-83+ or TI-84+ [SE], then that's what the students can only get. No parent will get their child a different calculator, because "that's what the sheet says." What games we write will have no effect on the market. Add to the fact that the majority of textbooks are
written for the TI-8x calculators, and there you have it:
monopoly. Unfortunately, Casio didn't have a chance from the start.** You would need an antitrust lawsuit to fix things.
Also, a good point was mentioned - neither the CX nor the Prizm have penetrated the market much. So technically, we're only programming for ourselves - not bad either! That means that most of us (at least the Ndless fans/people) will stay on 3.1 for however long they want. Remember, TI-loving teachers are
not 99% of the teachers in the United States (and those teachers should be fired on the spot). Also, most, if not all of the students, don't even know that they could update their OS! We're, in a way, quite safe from TI...
Again, I suggest we take the road where iOS jailbreaking has done - "new OS update? Great! Let's hack it again!" The JB community there doesn't even bother to convince Apple.
Sure, we're not as popular as iOS jailbreaking, maybe even less than Prizm hacking or TI-8x hacking. But who said we needed popularity to get stuff done?
We can do stuff at our own pace - this has always been the way in the TI community.
The most important thing is this: having fun. I know it sounds cheesy, but everything here is all done on a volunteer basis - we might as well have fun while doing so!

** There's definitely a more optimistic opposing viewpoint...

I'm just not a fan of Casio, that's all.