I don't really understand the grounds for removal unless there is some kind of intent to coerce players wishing to complete their classic collection using player gold. I don't like to speculate though.
Anybody with an inside track know if there was any officially-stated reason?
Cheers to all and thanks to any potential answerers!
Year of the Phoenix packs are A LOT better, because:
1. You can actually use the cards in Standard
2. You can get a lot more cards than Classic packs. Me personally, since I returned to Hearthstone at Scholomance expansion, I couldn't get good enough amount of Outland cards. The packs allow me to obtain cards from Outland for free instead of the powercrept Classic cards.
3. Combined with new-card-guarantee system (forgot the actual name), you can be sure to get cards that you haven't gotten, be it from Outland, Scholomance, or Darkmoon.
I even wish they would just sell that pack alongside the expansion-specific packs.