[blueimp]

Agreed - in addition to performance issues, there are also security issues if .htaccess support is enabled - because they can override security settings.

Originally the PHP example code didn't have a .htaccess file - I trusted developers that they would configure file uploads securely by themselves, e.g. via Apache configuration files.

The reason I added it was to support developers on shared hosting plans without access to the Apache configuration - something which was very common back then.