Producing a new system variable and a new token for retrieving the current language of the current user/logged-in user will reduce a huge amount of development time.
Currently, we are doing multiple workarounds for that, from a page point of view for visibility conditions especially we have to set the language inside the object to match the language or use some CSS or JS to hide/show an element.
From a Microflow point of view, we have to retrieve the language from the current user and match it. instead token or system variable will be much faster/easier to use.
I agree, and I think adding it to the Conditional Visibility would improve multi-language support as well (e.g. display different attributes, each containing data in a certain language)