This is the error I get on a clean Shopware 6.4.13 system when I clear the cache via console.
"User Deprecated: Since shopware/core : Class Shopware\Storefront\Event\ThemeCompilerEnrichScssVariablesEvent is deprecated. Use Shopware\Storefront\Theme\Event\ThemeCompilerEnrichScssVariablesEvent instead."
Any ideas whats going on at the Showpare HQ or am I doing something wrong here?
You're not doing anything wrong, this is merely a new strategy to more openly communicate deprecations. If you see this message the error_reporting of your PHP instance you use in CLI is set to also report "errors" of type E_DEPRECATED. You can change that in your php.ini to be less verbose.
As @j_elfering already said this is still subject to change but for now you can also add the --no-debug option to suppress the deprecation messages:
bin/console cache:clear --no-debug
The message you got is "only" a deprecation message, that does not indicate an error.
The reason is that the event was refactored, but for backwards compatibility currently the old/deprecated event and the new one are both thrown. Starting with shopware 6.5 the deprecated Event will be removed and the message will not appear anymore.