I can understand zip, 7z, and tar. But RAR? My only experience with RAR files comes from malware and warez (illegally distributed software, often compromised). Perhaps my own experience is just biased.
Though i rarely distribute stuff in RAR.
Also use it to span backups across multiple archival M-Disc blurays.
I also prefer the UI and configurable dictionary size to 7zip. Rar lets you isolate each file if you wish instead of solid compression. Ever had to insert 2 blurays just to get a 3kb text file out of an archive?
But yes, the only people who use it these days are the people who started using it long ago and just never switched.
Safely letting users easily see what's in a suspicious RAR before just blindly extracting it or opening it in third party software (possibly with known/unknown exploits) sounds like a good security feature for an OS.
7z does this now, so it is legacy stuff I come across I use RAR for. I am not aware of any advantage for RAR over 7z. I rarely have to use multivolume these days anyways.
In-file forward error correction[1]?
Same thing could be said about .mkv (Matroska), which is also natively supported by Windows. I've never seen it used outside pirated movies.
OP: rar is very very common for anything made by a Linux computer.
As sibling commenters said, you're probably thinking of .tar. Now that I run into a lot. :-)
I probably installed it many years ago from the repositories. Now that linux gaming is so good I've been seeing 7z and rar being used for game mods a lot.
If you're on Linux, you make .tar.gz or .tar.bz2 or something. Or .zip, I guess you see sometimes. But RAR? That's a windows people thing, in my experience.