Yes, you can delete the WP-Better Security folder and that gets rid of the plugin, but just before you do that, try restarting the plugin from your “installed plugins” list, iThemes needs to be rebooted especially after updating the banned users list.

Also, remember to whitelist your own IP address.

Hope that helps

Just deleting the better-wp-security folder is not recommended as it doesn’t clear the plugin database metadata.

ALWAYS delete plugins from the Plugins page in the Admin Dashboard.

Renaming the better-wp-security folder might help restore access to the Admin Dashboard when all other options failed.
Once back in do follow the recommended uninstall procedure after renaming the plugin folder back to its original name…