Laravel file storage URLs work locally but 404 on a real server - php

Question

I'm working with a custom file storage disk and it works as expected on my local machine, but on my Forge server the generated asset URLs don't work.
My filesystem config looks like this:
'disks' => [
'local' => [
'driver' => 'local',
'root' => storage_path('app'),
],
'public' => [
'driver' => 'local',
'root' => storage_path('app/public'),
'url' => env('APP_URL').'/storage',
'visibility' => 'public',
],
'assets' => [
'driver' => 'local',
'root' => storage_path('app/public/assets'),
'url' => env('APP_URL').'/assets',
'visibility' => 'public',
],
];
I have a file at {myapp root}/storage/app/public/assets/file.jpg and I'm generating URLs with Storage::disk('assets')->url('file.jpg'); and this works fine, it gives me the expected URL, which is (locally) myapp.test/assets/file.jpg. In production I get the correct URL as well, myapp.com/assets/file.jpg, but this link 404s. If I insert "storage" into the URL, so that it's myapp.com/storage/assets/file.jpg, it works.
I've php artisan storage:linked everything in both environments, everything else is exactly the same, but on a real server the URLs all 404.
UPDATE SEP 2020
I have a much simpler filesystem setup now, but IIRC the solution here in the end was just to symlink public/assets to storage/app/public/assets on the Forge server. At the time this was ugly to do automatically, but in Laravel 7+ (maybe earlier too) there's a new links key in config/filesystems.php that makes this very easy.
In general, I wouldn't recommend nesting public disks/symlinks like this though. I should have just put things in storage/app/assets and kept it flatter overall.
It's still a mystery to me why this all appeared to work fine locally...