Windows 11 has the option to protect parts of your filesystem. You may want to enable that.
Why? Because otherwise, pretty much any app with the exception of those locked in a web browser can read anything in userspace on your pc. Which is basically everything unless you've taken extra steps.
That's been the norm for quite a while, and unlike android, microsoft is hesitant to ditch the old thing and add in a prompt "app x is asking for file permission (yes/no)" because they want old software to work with new things.
On for linux, you'll have to make an extra user, install acl support and pray it doesn't accidentally get written incorrectly by some random app. That is, if you get something like hexos for example. You can roll your own as well.
On mac, don't bother. Apple has been caught routinely lying about their security and just straight up not fixing major security flaws. Dump your stuff on an external drive and unplug it when you're done. That goes for their desktops and phones.
edit: inb4 "whats on your iphone stays on your iphone"