Are Certain Skins Rarer Than Others?

There's only one skin in the whole game I want. I'm a diehard Phoenix fanboy, so The Warbird Resurgent is 100% my jam. Once I found out it exists, I've only played Sorcerer since I heard the skins are weighed by class play time.

It's been six weeks of checking the store every day, and I still haven't seen it. Am I just unlucky or is there something I'm missing? I only started playing D4 this season so is that an issue since the skin released in Season 7?