You ended up with full disk encryption. For most people, it's the simple option, everything is encrypted. That means the OS can't start without the key, because you're the only holder of the key. It's both dead simple, and pretty bulletproof since there's no way to access the system without the password. But as you said, not everyone wants that.
What you're asking for is an encrypted home directory. It's not that Linux can't do it, it's just not what you got. Depending on the use case you can either use TPM to unlock the root partition to boot, or not encrypt the system itself. Then when you log in, it decrypts a separate partition (or use ZFS native encryption, or use fscrypt if your filesystem supports it, or use an overlay filesystem like go-cryptfs).
So it's not that Linux doesn't support your use case but rather your distro doesn't offer it as an installation option. From there you either configure it yourself (ArchWiki is great regardless of distro), or seek out a distro that does.
Linux is not an operating system, it's just the kernel. What makes it an OS is what distros build on top of it. Linux alone is not that useful, hence the basis of the GNU+Linux memes: it's Linux, plus a lot of GNU tools to make it do useful things, plus a desktop environment and a whole bunch of other libraries and applications, plus the distro's touch tying it all together in a mostly cohesive experience.