I wouldn't call it FUD, but the features that you describe are certainly becoming less and less necessary, in part due to what you already mentioned. However, CCleaner is a useful tool, if you know how to use it.
I regularly use it to fix installation issues where the installer will not work due to some leftover registry entries. Now I can go in manually to hunt them down, or do a sweep with CCleaner and let it do the grunt work--I have yet to see it fail to find what I'm looking for.
Of course, it also features a quick way of disabling startup items and from a (albeit on a low level) privacy aspect, the selective cookie cleaning is also nice. You can also download a community-built ini file that adds a lot more features to the cleaning tool, which is useful if you are a particularly obsessive cleaner.
Whether or not it aids performance, I don't know, as I haven't run any benchmarks. Perhaps placebo effect, but I do notice when I run it on client's systems who are not particularly IT savvy that the performance has increased substantially. On my own system, where I run it more regularly, I do not notice the slight performance boost it may warrant.