can i change the admin user without issues?

[Efficient_Good_5784]

Negative.  The account you created during the initial setup is THE admin.  You could do some database hackery to change this, but that is not recommended.  You can either manually tag shows/movies as watched or use something like Trakt to sync your watch status externally and then pull it into the new user.

Is this true? Is there something in the code that has admin status hardwired to the first OG account?

I also was in the same boat (created the first admin account as my personal account).
I wanted to transfer over my watch status, so what I did was create a new account named "admin".
I then gave it permission to manage the server (Dashboard > Users > Account > "Allow this user to manage to manage the server") as well as allowed it to delete media from all libraries and the rest of the admin things too.
After that, I logged into the new admin account and disabled server management and media deletion for the original first account.

Now my OG first account can't access the dashboard or modify/delete any media (except for playlists which is a bug that will be fixed soon).

Also, I was playing around with this on my backup Jellyfin server before doing it on my main server, and I found out that Jellyfin would prevent you from doing the dumb action of removing server management rights from yourself if your the only one with server management rights. You'll just be presented with an infinite loading circle until you reload the page unless another account is present with access to the dashboard.

My question is then, since you state that the first account is the admin account, is there somewhere in the database that still says my account is the admin, but with permissions disabled?
My media library at this point still is small enough to where I can go and just mark things as watched, so would there be any benefit in just renaming the 2nd "admin" account I made to be my new personal account, then change the first OG account to actual "admin"?