I'm not going to play guessing games regarding the future of Bitcoin. It is however a fact that as the value of something increases, the effort that goes into protecting that thing increases.
Actually, as has been stated, for the value to increase, it will require wider adoption. Wider adoption means the value is spread among more users. And the key point here is: when you have 1 million users who possess a digital file that contains 100x where x is valued at y, or 100 million users who possess a digital file that contains 1x where x is valued at 100y, you still have the same total value per user, and thus, rationally, each user applies the same measures to safeguard it, regardless of the value of a single unit.
Honestly, is that your argument? That the increased value of Bitcoins will result in an overall increased effort to safeguard it?
Distribution of bitcoins is not homogeneous. That is your first invalid assumption. Some people will have a lot of coins and will in all likelyhood be willing to spend some of it to create additional security infrastructure for Bitcoin. I can't imagine any security infrastructure good only for those with lots of bitcoins, or any benefit to them for keeping it to themselves. Especially since greater security could lead to greater adoption and a higher price.
Yes, that is my argument. What is your aversion to creating a fork with your changes?