Changing home directory wiped previous account?

If you have another macOS user admin account, then you can use it to fix your mistake by using the instructions in this Apple article for changing the name of the user account:

Change the name of your macOS user account and home folder - Apple Support

If you don't have another macOS admin user account, then you will need to trick macOS into running Setup Assistant again so another admin user account can be created by using the instructions in this article written by a respected forum contributor:

Restarting Setup Assistant to create Admin user account - Apple Community

Make sure to follow the instructions in both articles carefully. Every step & detail mentioned in the official Apple article for changing the macOS user name is absolutely necessary & critical.

FYI, be extremely careful whenever you are accessing anything listed as Advanced, or an Option which has been hidden by macOS by default. And always make sure you have a good backup before making any major changes to the system. You should always have frequent and regular backups of the computer and all external media (including the cloud) which contains important & unique data. There are a lot of new ways to lose access to your data with the newer systems due to major changes to the hardware, software, and security changes. If you had made this mistake while using macOS 14.x Sonoma, you would be needing to completely erase the whole Mac followed by reinstalling macOS & restoring from a backup since Apple broke the option to trick macOS into running Setup Assistant again.

Hmm, there's more out of whack here than I first noticed. You don't even have the menu bar at the top of the screen. There is an option to hide it, much like the Dock, but I presume you didn't do that.

Fortunately, you can still access the settings. Click on the desktop, then press Command+, . Turn on the option to show Hard disks.

You can then close that box.

Now that you can see the main drive, double click that. By default this is all you should see at the root level:

If not, what else is there?

Then open the Users folder. Do you see anything other than the default Shared folder, and one user account?

But mine was just johnappleseed.

User accounts are expected to be in the /Users folder. By eliminating that part of the path from your name change, you told the OS to create johnappleseed a level down, next to Applications, Library, System and Users. It will never find, or look for a user account there.

It may not have created/moved johnappleseed there at all. But instead, possibly, deleted the entire folder. Or, since it can't really create a user account at the root level, it simply made a new user account in the correct location.

Check both the root level and the Users folders. Is there anything out of place at the root level? Is there more than one account now in the Users folder?

That is normally protected for changes.

• What is the version macOS?
• How did you make such change?