Bug 6100 - "Allow different directionality (rtl/ltr) for user interface and wiki content" is an old one. It goes back all the way to 2006. Many people commented over time and several issues mentioned have already been overcome.
By raising the priority of this bug to "highest" and "major", a clear signal is given by the Wikimedia Foundation that support for languages like Arabic, Farsi, Hebrew is important. Actions like this and the recent work on the implementation of Narayam demonstrate this support visibly.
Support was announced in words but these actions speak for themselves and empower the words with reality.