Hopefully a change like this will be made in the future, but for now, this is the soft cap for perks and sensitivity. Given that you do just keep accumulating extra points after spending all you can, I have to imagine that there are plans to change this system a bit in the future.
It could be fun to be able to reinvest sensitivity points into your core stats once reaching a certain level, but those are capped at 100 for now (which could also change, since monsters don't seem to have stat caps like that). I wish sensitivities could just be lowered further than they currently can, honestly. The more I level, the stronger I want to be!
Anyway, I'm glad you brought this up. We can only cross our fingers that a solution will be provided!