This begs the question, why leave in something that no longer works properly?
It should work proberly, but it won't receive any additional features and development anymore. And it is there because some people are really, really, really scared of anything that looks like a formula or programming, even if just the remotest. There are people that wouldn't want to touch and learn formulas in Excel, even if it would make their life so much easier and save a lot of time.
For these people, the condition designer is there and makes sense.
Now for anyone who wants to do stuff that is a little bit more advanced than just basic conditions, we highly recommend to ignore the Condition Designer and learn the basics of Expression Script /Manager. Even if you might be able to do the stuff in the condition designer, if you have a basic idea of Expression Script you will be so much quicker in applying conditions to questions, that you will never want to touch the condition designer again. Thats why.