cEDH is a game of mana efficiency, and while two mana per activation isnt insignificant, it sure is a whole lot better than four, especially when it pays for half of the cost via a new land in play every now and again
Once the possessed person consumes human flesh, their body begins the transformation into the monstrous creature we know as the Wendigo
Rubinia Soulsinger can steal creatures in a pinch, and our Training Grounds/Heartstone/Biomancer's Familiar strat is great with Memnarch
You often want many creatures that mutate in the same deck to maximize the synergies, so Souvenir Snatcher doesnt go in just any deck
Playing a card like Virtue of Loyalty or Virtue of Persistence just to hard cast the enchantment probably wouldnt be viable
Unfortunately, this price hike will also play a role in raising the bar of accessibility to the Standard format - a bar which was already prohibitively high to begin with