wikipedia.gr domain had been squatted for more than a decade, displaying a copy of greek wikipedia, it had enough traffic and there are still links to it. (I have seen people in workshops typing "www.wikipedia.gr")
It has finally been acquired by the WMF.
Creating a redirect from wikipedia.gr and www.wikipedia.gr to el.wikipedia.org would be helpful for those readers that do not know the exact url of wikipedia and expect that the greek wikipedia would have a .gr domain. Greek is the only official language of Greece and mother language of 98% of the population (and understood by the rest 2%).
Several other domains such as https://wikisource.gr already redirect to the corresponding projects (el.wikisource.org)