The synergy with Devoted Druid has made Luxior, Giada's Gift very popular amongst modern and commander crowds. That's why the price correction has been so smooth on the market.
There is also a great interest in this card from the White Blue Stoneforge players, who happen to run a lot of planeswalkers that could benefit greatly from this tiny artifact.
It looks like there is a potential for growth here, but not a huge one. So it's better to wait and see if all this hype gets justified or not.