I've heard that the ext4 filesystem does not need to be defragmented because the way it stores information is engineered to avoid exactly that problem.
At them same time, I have a program called Bleach Bit, which is essentially the Unix version of CCleaner for Windows, except a lot more detailed and advanced (not to mention several times faster).
For a few months now I've been running BB before shutting down, but if clutter and fragmentation generally is not a problem for Linux and ext4, then is there really a point to using Bleach Bit? Or could I just install it once a month to do a clean, and then immediately uninstall it?
I'm not quite savvy with the deep innards of the filesystem, so a detailed technical explanation would be great if possible.