Android still doesn't support many compression types
When w11 announced that they were adding native support for rar, 7z, etc, it occurred to me that android also doesn't support these and I found it really weird
Google wants you to handle all your storage needs through Drive and Google Photos, where they are in control, can scrape more data, train models on your photos, and push you onto paid storage plans.
I can't really see the benefit to Google in having an excellent local file manager with wide archive-file support. It doesn't profit them in any way that I can think of.
Thankfully the workaround isn't too bad, just installing an alternative file manager.
Google isn't exactly excited about the concept of local files. They would prefer you to keep everything in their online services.
If you need support for these, then installing a separate file manager app is your best bet.
I'm using this one:
https://f-droid.org/packages/me.zhanghai.android.files/
(No idea, though, if it supports unpacking RAR archives.)