I remember using this a lot in my first year of migrating from Windows to Linux. It was engrained into me that my system will degrade if I don't "clean" it regularly, like on Windows.
Old registry entries definitely slowed Windows down all the way up to Windows 7. I'm not sure if they fixed it with 8 or 10, but I don't think so since 10 slows considerably after just a few months.
Unless you desperately need to free up room in your tiny SSD to make room for Baldur's Gate 3. I recently used a tool like this to get rid of a bunch of old logs and things and managed to free up tens of gigabytes of precious space.
I do still like to clean out ~/.cache from time to time, often because of the thumbnail cache (which more or less rebuilds itself to the same size within a few days, so kind of pointless sometimes).
No need for an application, though. Just an alias (well, abbreviation in fish) when I feel it's getting too much.
It's completely pointless for anything else. This does remind me to check for empty or left over ~/.config and ~/.local/share folders, though. Haven't cleared those out in a while.